UFiber v4 Python Client

Yeah, I finally remembered to make a post about this. I know it will like as a copy-paste of the previous one, because, in fact it is.

Ok, if you have been following the series, you should already know that I equally love and hate UFiber OLTs. They are affordable, deliver a lot of bang for the buck, and have an awful GUI.

Well, the GUI is lovely on v4.

Python in the middle

I wrote a quick and dirty client which acts as a sort of middleware between the HTTP inteface of the OLT and you.

It allows to provision non existing ONUs, GPON profiles, WiFi profiles, retrieve active ONU status and general configuration.

Take a look to it on https://github.com/baldoarturo/ufiber-client-4, and feel free to contribute if you want to.

How to help

It would be awesome to have docs ūüėÄ

Are you a pydoc master? Let’a add docstrings.

Do you have an OLT for me to test? Ping me and we can set up a VPN.


This is the core of the project. It uses the OLTClient class to provide a middleware between you and the HTTP interface of the OLT.

Initialize a new OLTClient instance with:

client = OLTClient(host='', username='ubnt', password='ubnt', debug_level=logging.DEBUG)

Required params are only host, and credentials.

The initialization will handle the login for you, altough you can call the login() method manually.

If the OLT is network reachable, and you have provided the right credentials, and the OLT GUI is alive and well, you should be ready to start.

What changes on v4

Well, UBNT got rid of the GPON profiles. ūüôĀ

This software is intented to give you an alternative by keeping profiles as JSON in the ./profiles folder.

You can copy the template.json file and make your way using it as a starting point. It should be self descriptive.

There is an schema.json which validates your profile before pushing changes into the OLT.

UFiber Python Client

Ok, if you have been following the series, you should already know that I equally love and hate UFiber OLTs. They are affordable, deliver a lot of bang for the buck, and have an awful GUI.

Please, be aware that this can change for better or worse in the future, and at the time I’m writing this the latest firmware is v3.1.3. I trust in you UBNT, hope you can sort out this and give us a better product. I’ll keep my fingers crossed.

Python in the middle

I wrote a quick and dirty client which acts as a sort of middleware between the HTTP inteface of the OLT and you.

It allows to provision non existing ONUs, GPON profiles, WiFi profiles, retrieve active ONU status and general configuration.

Take a look to it on https://github.com/baldoarturo/ufiber-client, and feel free to contribute if you want to.

Edited on Aug 15 2020: I did the same for firmware version 4, which is cleaner and fixes a lot of bugs. Stay tuned!


This is a quick dirty project built to provide a quick dirty client for Ubiquiti UFiber OLTs, using firmware version 3.x

There is also a CLI attempt, but I couldn’t find any ready to use packages to build a decent CLI.

More info about what am I doing this is on the following entries:


This is the core of the project. It uses the OLTCLient class to provide a middleware between you and the HTTP interface of the olt.

Initialize a new OLTClient instance with:

client = olt.OLTClient(host, username, password)

The initialization will handle the login for you, altough you can call the login() method manually.

If the OLT is network reacheable, and you have provided the right credentials, and the OLT WEB GUI is alive and well, you should be ready to start.

You can also connect using cli.py:

$ /cli.py
UFiber Client for fw version 3.1.3
UFiber> help

Documented commands (type help <topic>):
connect  help  onu  quit  show

UFiber> connect
Logging to ...
Connection OK


In a previous post we took a quick look to the Ubiquiti UFiber OLT. As always, UBNT tries to offer a non expensive solution to provide last-mile conectivity for end users. I am using non-expensive because UBNT gear is not cheap. Yeah, it can be affordable, but you only get what you pay for.

We saw that the command line is very limited, even when the software is a fork of Vyatta. There is no way to get ONUs provisioned from the command line, so forgot about Ansible (we love Ansible), netmiko, and other SSH clients tools to ease your life.

UBNT wants you to use the web GUI, period. They offer a dockerized management system called UNMS, which really comes handy after you have provisioned your customers.

Both you and me, as network operators, know that provisioning customers is one of the more boring tasks, but is is still a critical one. Fast and precise provisioning translates in more customers, more stability, faster troubleshooting, and peace of mind.

Yeah, SONAR exists, but not all operators can work with their pricing and technology supports. And don’t even think to integrate billing if you are using electronic invoicing with AFIP in Argentina.

If you are still here, don’t give up. If there is a will, there is a way.

Under the hood

The OLT has a web GUI served by HTTPS, with a self-signed certificate, on port 443. There is no easy way to use a proper certificate here, but well, it’s something.

If you are not authenticated, this is what waits for you in the URL root.

Looks like a login screen

I want to know if this is a standard HTML form. And indeed it is.

<form id="LoginForm" method="post" class="ui-form">
    <input id="Username" name="username" class="text-input" type="text" placeholder="Username" autocapitalize="off" autocorrection="off">
    <input id="Password" name="password" class="text-input" type="password" placeholder="Password">
    <input id="LoginButton" class="submit-input ui-button ui-widget ui-state-default ui-corner-all" type="submit" value="Login" role="button" aria-disabled="false">

What happens when we log in? I’m using Chrome version 81 and something, let’s open devtools to see the network activity.


Request URL:
Request Method:
Status Code:
303 See Other
Remote Address:

Request Headers

Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,/;q=0.8,application/signed-exchange;v=b3;q=0.9
Accept-Encoding: gzip, deflate, br
Accept-Language: es,en;q=0.9
Cache-Control: max-age=0
Connection: keep-alive
Content-Length: 32
Content-Type: application/x-www-form-urlencoded
Cookie: PHPSESSID=5da99950e9f74ad8b727f219c9e41d76; X-CSRF-TOKEN=9f0c78e2ea8994b39834e0241466c21b68a28df59bf98364ece91dcd183bdab5; beaker.session.id=29fdb5243db8446f81f75587c9c2a722
DNT: 1
Host: x.x.x.x
Origin: https://x.x.x.x
Referer: https://x.x.x.x/
Sec-Fetch-Dest: document
Sec-Fetch-Mode: navigate
Sec-Fetch-Site: same-origin
Sec-Fetch-User: ?1
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36


Content-Length: 0
Content-Type: text/html; charset=UTF-8
Date: Fri, 02 Jan 2015 08:54:30 GMT
Location: https://x.x.x.x/
Server: Server
Set-Cookie: PHPSESSID=a24b5cbbd6874a1eb09c2d086a93efc6
Set-Cookie: X-CSRF-TOKEN=6f13035a0b7aa4b375e6798c7c60f12e805ecea8c74a3306da81c710e6a3701b
Set-Cookie: beaker.session.id=a24b5cbbd6874a1eb09c2d086a93efc6; httponly; Path=/; secure

Form Data

username: ubnt
password: ubnt

So, this is a standard POST. And we got a cookie.

This can be translated to Python by using the request module.

host = 'olt.ubnt'
url = 'https://{host}'.format(host=host)

USER_AGENT = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36'

    'Content-Type': 'application/x-www-form-urlencoded',
    'User-Agent': USER_AGENT,

form_data = {
    'username': username,
    'password': password,
response = requests.post(

Good enough for me. Of course this should be into a try/catch structure, but ymmv.

Shut up and take my ONUs

So, we are logged in. What about ONU configuration? The GUI allows to update firware, but this is done automatically starting from software version 3.1.3. We can also set many parameters of the ONU configuration, and provision them via OMCI, but the ONU should already exist in the ONU list.

Configuring existing ONUs

There is no way to add non-existing ONUs to the configuration, which makes pre-provisioning impossible.

What happens when we click on save?

A POST request is made, passing an interesting payload to the /api/edge/batch.json endpoint. Let’s see how does it looks like.

This POST puts a payload with all the ONU configuration, and a bit more. It uses a JSON structure which looks like this.

    "SET": {
        "onu-list": {
            "UBNTffffffff": {
                "disable": "false",
                "profile": "profile-2",
                "name": "ARTURO TEST",
                "wifi": {
                    "provisioned": false,
                    "enabled": true,
                    "ssid": "UBNT-ONU",
                    "hide-ssid": false,
                    "auth-mode": "wpa2psk",
                    "wpapsk": "",
                    "channel": "auto",
                    "channel-width": "20/40",
                    "tx-power": "100"
                "pppoe-mode": "auto",
                "pppoe-user": "ARTURO",
                "pppoe-password": "ARTURO",
                "wan-address": "null",
                "port-forwards": []

Of course this is a fake ONU with a UBNTffffffff serial number. Yeah, we can fool the GUI and send whatever values we want.

This comes real handy because you can pre-provision ONUs before they show up in the PON port.

As an ISP, this means a time saver, because you can deliver ONUs ready to plug and play, and the OLT will hand out all the configuration without further intervention.

The web GUI is handy (altough not so stable), but it really doesn’t makes sense to have to manually provision each ONU when they are connected in the PON port.
Technicians have to spend to a lot time on customers houses waiting for the NOC to configure each new customer. This is no-bueno in pandemic times. You want to install as many new customers as possible, as fast as possible, and staying in foreign homes as less as possible.

It seems it’s time for me to code something.

If you are reading this, Robert Pera, please make me a CLI.

Digging into Ubiquiti’s UFiber OLT

As some of you might know, currently I’m working as a network engineer on a medium size ISP. The company had a long history working as a WISP, and in later times they moved into FTTH, trying several vendors among the lead players of the industry.

As some of you might also know, Argentina has a history of economic meltdowns, currency devaluations and import restrictions. Considering this, the best solution to implement a network here is usually the one you can afford, which can provide the performance you need, and over all things, the one you will be able to keep buying in the future.

So, considering all these factors, when planning for a GPON network for a medium size operator…while trying to keep costs low for both the company and customers:

  • It really doesn’t matter if Calix supports XGS-PON technologies…
  • Or if Huawei gear is compatible with almost everything…
  • Or if Furukawa Electric has some great management software…

The real questions to ask were:

  • Can the company afford the OLTs, and the ONUs for the planned customer base?
  • Will they be in the market in the years to come?

Enter Ubiquiti UFiber

UFiber offers internet and telecom service providers a cost‚ÄĎeffective fiber optic delivery system for Triple Play Services (data, voice, IPTV/VoD) with speeds of up to 2.488 Gbps downstream and 1.244 Gbps upstream.

OLTs come with dual hot-swap power supplies, 4 and 8 PON ports versions. Every PON port supports 128 CPEs, 20 Km maximum range. The uplinks are two SFP+, which can with in LACP.

The ONUs options, at the time when I’m writing, are:

  • UFiber Nano – one PON (of course), one Gigabit Ethernet, a fancy LCD display. Passive PoE powered.
  • UFiber Loco – a PON, a Giga Eth, passive PoE powered or external micro USB power.
  • UFiber Wifi, like above, but with 4 Giga Ethernet ports, and a 802.11n interface.
  • UFiber Instant, a nice SFP ONU.

Ok, sounds nice. How do we manage them? There is a web GUI…

Hey, the GUI looks like EdgeOS !

Once logged in, the GUI has a nice dashboard which looks like this. And it crashes from time to time.

They tried

But this not EdgeOS, the OLT is a different product! Let’s ssh into it to get the real feel.

ssh admin@olt
The authenticity of host 'olt (olt)' can't be established.
ECDSA key fingerprint is SHA256:thnWRB2bImsdNuu1ar74GryFwv5r7PoHJsHhJOkHnCQ.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'olt' (ECDSA) to the list of known hosts.
Welcome to EdgeOS
By logging in, accessing, or using the Ubiquiti product, you
acknowledge that you have read and understood the Ubiquiti
License Agreement (available in the Web UI at, by default, and agree to be bound by its terms.
admin@olt's password:
Linux olt 4.4.159+ #1 SMP Fri Feb 22 15:28:22 UTC 2019 mips
Welcome to EdgeOS
Last login: Tue May 26 15:50:16 2020 from

Ok, this is definitely EdgeOS. So we got a fully featured command line interface, with commands similar to Juniper JunOS.

admin@olt:~$ show configuration | display set
-vbash: display: command not found

Ok, maybe the command line is not so-fully-featured. No worries, I’ll write Ansible playbooks to manage the OLTs anyway. Most of the configuration is Juniper-like, so all I need at this moment is find out how to configure GPON profiles, and provision ONUs.

admin@olt:~$ show configuration | match onu
admin@olt:~$ show configuration | match profile
admin@olt:~$ show configuration | match gpon
gpon {

There you are! Let’s go into configuration mode.

admin@olt:~$ configure
admin@olt# show system gpon
isolation enable
mtu 1518

Well, this is awkward. There is nothing about GPON in the command line. Neither in the working configuration, and of course being Ubiquiti, there are no command line manuals.

Love the smell of undocumented commands in the morning

So, I saw two interesting lines before: Linux olt 4.4.15, and -vbash: display: command not found, which tells me this is Linux, not BSD as in Junos, and we have bash.

Possible completions:
  add           Add an object to a service
  clear         Clear system information
  configure     Enter configure mode
  connect       Establish a connection
  copy          Copy data
  delete        Delete a file
  disconnect    Take down a connection
  generate      Generate an object
  initial-setup Enter initial configuration dialog
  no            Disable or reset operational variable
  ping          Send Internet Control Message Protocol (ICMP) echo request
  ping6         Send IPv6 Internet Control Message Protocol (ICMP) echo request
  reboot        Reboot the system
  release       Release specified variable
  rename        Re-name something.
  renew         Renew specified variable
  reset         Reset a service
  restart       Restart a service
  set           Set system or shell options
  show          Show system information
  shutdown      Shutdown the system
  telnet        Telnet to <hostname|IPv4 address>
  terminal      Control terminal behaviors
  traceroute    Track network path to <hostname|IPv4 address>
  traceroute6   Track network path to <hostname|IPv6 address>

No signs of bourne again shells in the horizon. Does my magic have any power here?

admin@olt:~$ sh
sh-4.4$ whoami
sh-4.4$ sudo su

Finally a decent shell. Which world is this?

root@olt:~# uname -a
Linux olt 4.4.159+ #1 SMP Fri Feb 22 15:28:22 UTC 2019 mips GNU/Linux
root@olt:~# ls -l /etc/ | grep apt
drwxr-xr-x 6 root root 117 Feb 22 2019 apt

We have apt, so this is a Debian world. I checked on /etc/apt/ and there are no repositories, but I am sure I could run cowsay on this. But the fun can wait.

Where is my GPON configuration? It should say “onu” somewhere.

root@olt:/# grep -r "onu" / | more
grep: /proc/sys/net/ipv4/route/flush: Permission denied
/config/onu_config.json: "onu-policies": {
/config/onu_config.json: "onu-list": {
/config/onu_config.json: "onu-profiles": {
/home/admin/.history:show configuration | match onu
/home/admin/.history:show configuration | match onu
Binary file /lib/mipsel-linux-gnu/libbsd.so.0.8.3 matches
Binary file /lib/mipsel-linux-gnu/libnss_hesiod-2.24.so matches
Binary file /lib/udev/hwdb.bin matches
/lib/udev/hwdb.d/20-OUI.hwdb: ID_OUI_FROM_DATABASE=Monument Labs, Inc.
/lib/udev/hwdb.d/20-OUI.hwdb: ID_OUI_FROM_DATABASE=Optical Zonu Corporation
/lib/udev/hwdb.d/20-OUI.hwdb: ID_OUI_FROM_DATABASE=Presonus Corporation
/lib/udev/hwdb.d/20-usb-vendor-model.hwdb: ID_VENDOR_FROM_DATABASE=PreSonus Audio Electronics, Inc.
Binary file /opt/bcm68620/bcm68620_appl.bin matches
Binary file /opt/bcm68620/bcm_dev_ctrl_linux.ko matches
Binary file /opt/bcm68620/bcm_user_appl matches
/opt/vyatta/share/vyatta-cfg/templates/system/gpon/logging/module/node.def:syntax:expression: $VAR(@) in "main", "oltsys", "onu", "session", "events", "mon_th", "sdk"
/opt/vyatta/share/vyatta-cfg/templates/system/gpon/logging/module/node.def:allowed: echo main oltsys onu session events mon_th sdk

I bolded the interesting information.

  • There is a /config directory, which has a JSON file called onu_config.json
  • The operating system, is in fact, Vyatta.

If you are curious, this is the content of /config. We will dig deeper on the next article.

root@olt:/# ls -l /config
total 200
-rw-rw-r-- 1 root vyattacfg 3336 Jan 1 2015 2020
drwxrwsr-x 1 root vyattacfg 160 Feb 22 2019 auth
-rw-rw-r-- 1 root vyattacfg 3882 May 26 11:59 config.boot
-rw-r----- 1 root vyattacfg 2402 Dec 31 2014 config.boot.2015-01-01-0001.pre-migration
-rw-r----- 1 root vyattacfg 3151 Apr 13 2015 config.boot.2015-04-14-0130.pre-migration
-rw------- 1 root vyattacfg 187285 May 26 16:14 onu_config.json
drwxrwsr-x 1 root vyattacfg 232 Feb 22 2019 scripts
drwxr-sr-x 2 root vyattacfg 232 Dec 31 2014 snmp
drwxrwsr-x 1 root vyattacfg 160 Feb 22 2019 support
drwxr-xr-x 1 root root 160 Oct 29 2018 udapi-bridge
drwxrwsr-x 1 root vyattacfg 160 Feb 22 2019 user-data
drwxr-sr-x 3 www-data vyattacfg 224 Dec 31 2014 wizard

Using RSYNC with Ansible

The past week I found myself in a situation where I had to copy a directory to a remote SMB share, using it as a backup destination.

I didn’t had a login to the remote server, just a share and credentials for it, so the easiest way to sync all the data was to use rsync.

After I coded a small bash script to execute rsync, the business requirements changed, and this storage was indented to be used as an “offline” backup. Of course the best way to execute an offline copy is to set up an intermediate host, with the following steps:

  1. Mount a share from the intermediate server
  2. Copy the data to this share
  3. Unmount the share
  4. Mount the share in the destination server
  5. Copy the data from the share
  6. Unmount the share

By using an intermediate server, the source host of the data and the backup destination are never directly connected, meaning that a compromised origin server has no way to directly compromise the destination server, in the worst case scenario.

At the moment the intermediate server is waiting to be deployed, to I had to wrote a quick Ansible playbook to mount the remote share, copy the data, and unmount the share after the copy.

Instead of running rsync for the first copy, I suggest to run a standard copy because there is nothing to compare on the destination, and we will save some time and bandwidth.

An email notification was added to the playbook to get feedback about the synchronization result, as it was syncing about 1TB of data over a slow WAN link.

- hosts: remote_server
  gather_facts: no
  become: yes


    - name: Mount external storage
        src: //this_is_a_smb_path/on_another_server
        path: /srv/external
        state: mounted
        fstype: cifs
        opts: username=myuser,password=mypass

    - name: Rsync /srv/data to /srv/external
        archive: yes
        compress: yes
        src: /srv/data
        dest: /srv/external
      delegate_to: remote_server
      register: sync

    - name: Unmount external storage
        src: //this_is_a_smb_path/on_another_server
        path: /srv/external
        state: unmounted

    - name: Send e-mail
        host: my.smtp.server
        port: 25
        subject: Ansible Backup Report
        body: "Backup status is {{ sync.rc }}"
        from: Ansible Backups <ansible-backup@server.com>
        - notifications@domain.com

MikroTik VPN with Windows NPS RADIUS

With the advance of cheap MikroTik routers and ready to use CHR instances, setting up a VPN concentrator for remote access has become an easy task. Moving even further, a single router could provide VPN access and dynamic routing to integrate remote networks to the backbone.

I have started a gig as a consultant and sysadmin for a logistics insurance company, and one of my first proposals was to improve the network access for road warriors and remote workers.

The past

There was a Proxmox hypervisor, with some Windows 2012 R2 servers, providing Terminal Services, to execute a locally installed client for an ERP system. Proxmox was also using iptables on its the Debian backend of the to masquerade the VM networks with a public IP address, for Internet connectivity, dstnat rules for a NGINX reverse proxy, and RDP for the Windows servers..

I guess we all know having internet-exposed RDP is not a good idea, even if it is running in a non default port, so the former sysadmin transitioned to a SSH tunnel system, where the users connected to the hypervisor via SSH to establish tunnel to the desired server.

This solution, which I considered not elegant, was the only available at the moment due to networking constraints of the VPS provider, so really it was the best they were able to do, and it worked fine for them.

Over the Proxmox hypervisor, they also had a MikroTik CHR instance, with a P1 license, which was used to make a L2TP tunnel to a RB2011UiAS-rm located on their HQ.

Networks behind the tunnel endpoints were routed with static routers, so I configured a quick multi-area OSPF routing system, with the directly connected networks on area 0, along with the /30 network of the tunnel. I added an additional area on both ends, for the future VPN networks. Once OSPF was working as expected, I remove the static routes.

Securing the tunnels

This interconnection via the L2TP tunnel was just plain ol’ L2TP, without IPsec. This is no bueno, and could be improved. Fortunately, IPsec configuration on MikroTik is trivial. Just select “Use IPsec” on both ends, and use the same IPsec pre-shared key.

Configuring via Winbox

This can of course be configured via CLI. Would you like some RouterOS configuration Ansible on next posts? Let me know in the comments.

/interface l2tp-server server
set authentication=mschap1,mschap2 default-profile=VPN enabled=yes ipsec-secret="PUT_A_SECRET_HERE" use-ipsec=yes

VPN profiles

It’s always a good idea to copy the default-encryption profile, and create a new one based on that template. I set up a local address which was of course, part of the networks announced in a separate area by the OSPF process. I also added a IP pool to be able to provide dynamic addresses for the VPN users.

PPP profile

Maybe you are aware that in the Cisco world, you have to use tcp adjust-mss to adjust the maximum TCP segment size, to advoid fragmentation of packets over the tunnel. Fortunately, this is configured by default on RouterOS.

We don’t want any fragmentation

Finally, to be able to redirect the dial-in to a RADIUS server, we need to instruct the PPP AAA system to use RADIUS, as shown next.

Setting up RADIUS authentication

RADIUS servers are very simple to set up on RouterOS.

Under the RADIUS submenu, add a new server for PPP service, and configure the following parameters.

  • IP address of the radius server
  • RADIUS secret
  • Authentication and accounting ports, usually 1812 and 1813. Some servers use 1645 for accounting. Those are all UDP.
  • REALM if your server supports that extension
  • Which source address should the router use for its NAS-IP-Address
Configuring RADIUS

Using Windows NPS as a RADIUS server

NPS can work without a Certificate Authority but if you are working in an Active Directory environment, you’ll save a lot of headaches by installing the CA role.

Installing NPS and CA
Selecting Roles

In my particular scenario, the server was not part of a domain so the certificate generation and association was skipped.

Once the roles have been configured, I headed to the NPS service configuration, and add new RADIUS client.

Make sure to match the RADIUS secret and the source IP address as you configured on the MikroTik side.

New RADIUS Client

Next, the network access policies. I wanted to match the NAS IPv4 address, and the authentication types. If you are not familiar with the RADIUS lang, NAS stands for Network Access Server, which in this case, is the MikroTik router which provides the VPN service.

MikroTik source address

I had to use a CHAP fallback due to some legacy devices withuout MSCHAP support.

Authentication methods

Next, I added a new Access condition, matched the NAS address once again, and selected the local server as point of authentication.

Authenticate on this server

Once everything was properly configured, I set up the VPN client on my side, which looks like as follows. The idea of using NPS as RADIUS was to be able to use my Windows account credentials for the VPN.

VPN client on Windows 10

I verified the successful authentication on the router logs, and the VPN was sucessfully connected.

Creating passwordless logins with Ansible

What kind of users? Well, a special user called Ansible, which will use SSH keys to login into remote devices, allowing for full automation on playbooks.

Creating a new key

If you have been following the series, maybe you remember that we already created keys on the Juniper Junos SSH Keys post.

To create a new key, let’s issue the ssh-keygen command as follows. The -f flag tells the output path, and the -C flags specifies a comment.

$ ssh-keygen -f ansible.key -C ansible-login-passwordless

This should output two files, ansible.key and ansible.key.pub.

The public key should look something like this.

$ cat ansible.key.pub 
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCtJUPfzJY6vKqLUssPPQe+LD7qRmIPbVhb/1i4Qab7T0Vf3x+ItfJyV4Ej4FsnRSU8iMU8J5eIdcetGQfsmwIZAm8glB0T6En5F9lvq2Yd+3RKIvxM3UlrIH6EaRedhsRUyV96CHfIO2nVqS9dmFfgrOJMIOwfTWIiRDNczUPw7aqw0FExslw9ZC0FO/1A6hYgofkGLrdIu9gK/WkNg5BE1EUCYPqbDBEHnnhv3C33LqiSJZnXJyqu53qz+jlv+1LZxerNHuovMGZMkjQsBo2f3r9Gk/9HqBmT0rcLr5prm4CqqryJ3S9VyVVlF599BlqYMuMjj+fCj277R8kSnLxl ansible-login-passwordless

Of course we need an inventory to use, which has the following content.

$ cat inventory.yml 
      ansible_ssh_user: ansible
      ansible_ssh_private_key_file: ansible.key
      ansible_python_interpreter: auto_silent

This inventory only has one host, localhost, and uses three main variables:

  • ansible_ssh_user, which tell Ansible to use the user ansible
  • ansible_ssh_private_key_file, which indicates the key for this user
  • ansible_python_interpreter, just to avoid non needed logs

The playbook will looks like this. Notice we don’t need to gather_facts here, and we will instruct ansible to use become to gain privileges on the destination host.

- hosts: all
  become: yes


    - name: Make sure we have a "wheel" group
        name: wheel
        state: present

    - name: Allow 'wheel' group to have passwordless sudo
        dest: /etc/sudoers
        state: present
        regexp: '^%wheel'
        line: '%wheel ALL=(ALL) NOPASSWD: ALL'
        validate: 'visudo -cf %s'
    - name: Create "ansible" user
        name: ansible
        comment: Ansible Automation User
        groups: wheel

    - name: Add ssh key
        user: ansible
        state: present
        key: "{{ lookup('file', './ansible.key.pub') }}"

First, we want to make sure there is a group called wheel which will group users with administrative privileges.

Then, the /etc/sudoers file will be edited by allowing the wheel group to gain privileges, with a failsafe using a visudo validation.

Once the group has been created, the new user will be created, and a SSH key will be added to it.

It seems allright, but, how should we run the playbook, if the default user is ansible and this user does not exists yet? Let’s give it a try.

$ ansible-playbook create-user.yml -i inventory.yml 

PLAY [all] ************************************************************************

TASK [Gathering Facts] ************************************************************
fatal: [localhost]: UNREACHABLE! => {"changed": false, "msg": "Failed to connect to the host via ssh: ansible@localhost: Permission denied (publickey,password).", "unreachable": true}

PLAY RECAP ************************************************************************
localhost                  : ok=0    changed=0    unreachable=1    failed=0    skipped=0    rescued=0    ignored=0   

It fails, as expected, because the ansible user does not exists in the host.

Well, there is a way to provide a one-time password by connecting a as different user. You will need to install sshpass with your favourite package manager, like apt install sshpass.

One installed, run the playbook once again with the following arguments:

  • -e “ansible_ssh_user=xxxxx”, where xxxxx is a valid user on the remote host
  • -kK, which tell Ansible to ask for a login and a sudo password
$ ansible-playbook create-user.yml -i inventory.yml -e "ansible_ssh_user=arturo" -kK
SSH password: 
BECOME password[defaults to SSH password]: 

PLAY [all] ************************************************************************

TASK [Gathering Facts] ************************************************************
ok: [localhost]

TASK [Make sure we have a "wheel" group] ******************************************
changed: [localhost]

TASK [Allow 'wheel' group to have passwordless sudo] ******************************
changed: [localhost]

TASK [Create "ansible" user] ******************************************************
changed: [localhost]

TASK [Add ssh key] ****************************************************************
changed: [localhost]

PLAY RECAP ************************************************************************
localhost                  : ok=5    changed=4    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0 

Awesome, we have sucessfully created a new user!

Let’s try to connect using the ansible user with its key, as defined in the playbook.

$ ansible -m ping -i inventory.yml all
localhost | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python"
    "changed": false, 
    "ping": "pong"

Stay tuned for more automation using Ansible.

Ansible and Juniper – SSH Keys and Prompts

On previous posts we’ve seen how to connect with Ansible using credentials stored in a inventory file, and using SSH keys for authentication.

However, it isn’t a good idea to store credentials in plain text files, neither have to rebuild your inventory when you want to switch over to key authentication.

A possible solution is to first ask for credentials, run a playbook to install the SSH key, and then use this key for authentication on later playbooks.

You can find all the files for this post on the following repo.


Variable prompts

    - name: "ansible_user"
      prompt: "Username"
      private: no

The vars_prompt section is used to prompt the user for information, which is stored in variables. System variables can be populated, for example the ansible_user and ansible_password variables, allowing us to provide credentials to connect.

Take a look to the new version of the uptime playbook.

- hosts: all
  gather_facts: no

    - name: "ansible_user"
      prompt: "Username"
      private: no
      unsafe: yes

    - name: "ansible_password"
      prompt: "Password"
      private: yes
      unsafe: yes

    - name: Get uptime
            - show system uptime
      register: uptime
    - name: Show uptime
      debug: var=uptime

We’re prompting for the username and password on the vars_prompt section. The private settings indicates if the user input should appear on the screen. The unsafe option allows to enter special chars.

The task to execute are:

  • Get system uptime via the junos_command module, with “show system uptime”
  • Print the result using debug

And the new (and definitive) inventory looks like this now.

      ansible_connection: netconf
      ansible_network_os: junos
      ansible_ssh_private_key_file: juniper-hosts.key
      ansible_python_interpreter: auto_silent

The ansible_python_interpreter variable is set to auto_silent just to avoid the warning about no Python interpreters on the remote end.

Let’s give the playbook a run, trying to login with user and password. If you have not been following the Ansible series, let me tell you that there is an user admin with a password of Password$1 on the router. Note that the password won’t be seen on the screen.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ansible-playbook junos-auth-with-key.yaml -i junos-hosts.yaml 
Username: admin

PLAY [all] ******************************************************************************************************************

TASK [Get uptime] ***********************************************************************************************************
ok: []

TASK [Show uptime] **********************************************************************************************************
ok: [] => {
    "uptime": {
        "ansible_facts": {
            "discovered_interpreter_python": "/usr/bin/python"
        "changed": false, 
        "failed": false, 
        "stdout": [
            "Current time: 2020-01-13 17:12:32 UTC\nSystem booted: 2020-01-13 14:55:46 UTC (02:16:46 ago)\nProtocols started: 2020-01-13 14:56:03 UTC (02:16:29 ago)\nLast configured: 2020-01-12 16:09:02 UTC (1d 01:03 ago) by admin\n 5:12PM  up 2:17, 2 users, load averages: 0.00, 0.00, 0.00"
        "stdout_lines": [
                "Current time: 2020-01-13 17:12:32 UTC", 
                "System booted: 2020-01-13 14:55:46 UTC (02:16:46 ago)", 
                "Protocols started: 2020-01-13 14:56:03 UTC (02:16:29 ago)", 
                "Last configured: 2020-01-12 16:09:02 UTC (1d 01:03 ago) by admin", 
                " 5:12PM  up 2:17, 2 users, load averages: 0.00, 0.00, 0.00"

PLAY RECAP ******************************************************************************************************************            : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   

Great, the prompts work.

What if we try to login with the user ansible we configured on the previous post? This user has an SSH key installed on the router, and the local private key is on juniper-hosts.key.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ansible-playbook junos-auth-with-key.yaml -i junos-hosts.yaml 
Username: ansible

PLAY [all] ******************************************************************************************************************

TASK [Get uptime] ***********************************************************************************************************
ok: []

TASK [Show uptime] **********************************************************************************************************
ok: [] => {
    "uptime": {
        "ansible_facts": {
            "discovered_interpreter_python": "/usr/bin/python"
        "changed": false, 
        "failed": false, 
        "stdout": [
            "Current time: 2020-01-13 17:32:05 UTC\nSystem booted: 2020-01-13 14:55:46 UTC (02:36:19 ago)\nProtocols started:
 2020-01-13 14:56:03 UTC (02:36:02 ago)\nLast configured: 2020-01-12 16:09:02 UTC (1d 01:23 ago) by admin\n 5:32PM  up 2:36, 
1 user, load averages: 0.00, 0.01, 0.00"
        "stdout_lines": [
                "Current time: 2020-01-13 17:32:05 UTC", 
                "System booted: 2020-01-13 14:55:46 UTC (02:36:19 ago)", 
                "Protocols started: 2020-01-13 14:56:03 UTC (02:36:02 ago)", 
                "Last configured: 2020-01-12 16:09:02 UTC (1d 01:23 ago) by admin", 
                " 5:32PM  up 2:36, 1 user, load averages: 0.00, 0.01, 0.00"

PLAY RECAP ******************************************************************************************************************            : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   

Excellent, by using the user ansible without password, it will fallback to the key authentication.

Ansible and Juniper Junos – Using SSH Keys

Previous posts introduced basics connection methods to manage Juniper devices using Ansible playbooks. The inventory files had sensitive information and credentials which should not be accessible to anyone.

SSH and NETCONF over SSH requires client authentication, for example with and username and password, which could looks like this:

admin> show configuration system login 
user admin {
    uid 2000;
    class super-user;
    authentication {
        encrypted-password "$1$./TeE4CZ$uAMigDedlRuuJgcZx4hYk0"; ## SECRET-DATA

If you are a frequent SSH user, maybe you are aware that there are other login methods besides using usernames and passwords. By using a key-pair, with public and private keys, a password is no longer needed. The public key is installed on the remote host, and the private key is kept on the control node.

Although by using keys a password is no longer needed, a passphrase can be used with a key, adding an additional security factor to the connection. In fact, using SSH keys with passphrases is considered best practice. However, a private key with a passphrase is less useful for scheduled automation tasks because an operator may not be available to enter the passphrase at the scheduled time.

Creating a Key Pair

A key pair is a set of two cryptographic keys, a public one and a private one. The public key, as its name says, is the one we expose to the public. The private key, must be kept in a secure location.

To create a key pair, lauch ssh-keygen on a new console and follow the prompts. This utility will create two files, which are the public and private keys. Use the -f flag to specify the destination of the output files.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ssh-keygen -f ./juniper-hosts.key
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in ./juniper-hosts.key.
Your public key has been saved in ./juniper-hosts.key.pub.
The key fingerprint is:
SHA256:Kc/MZ11dLlXpcrK9PKO4L6XzaTrdczaek1ydzaFTFXw arturo@arturo-ThinkPad-L440
The key's randomart image is:
+---[RSA 2048]----+
|              ..+|
|               oE|
|              . =|
|         .   o O.|
|      . S     @.B|
|       *   . * +=|
|        = o = = +|
|         o =.o.%+|
|           +X=o+B|
arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ls 
juniper-hosts.key  juniper-hosts.key.pub

Now that we have created the key pair, let’s examine them to find out how a key looks like.

This is the private key, which in fact is a plain text file with a RSA key inside it.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ cat juniper-hosts.key

And the public keys looks like this.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ cat juniper-hosts.key.pub 
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCfRe11M8nFYdAd5aLwjBI4a2yBbBbfPzpn3V50fR0FLpJYPOax5ayFJMPY90PwRTSYZpzVX36tYglgjDRVmWlN4QqI2dL7X994fGWf5LQsvCf3UTp+BVG3qQT/25O/bXs9rl4/kcts+5LA+xUzBGB0IkvWlggVqAkvKuxqQNYTSoO0FdnR96d2ZSvo2usIuh+McGREBK+In0ThW/Hhiqsb1qT7aNfbWDQtE3Fn+cW/a4fBV4iCJsL7UmJn8gZoFI0Ki8XXfXBvUBTIublnkM28zqG7YLr5wxM01Dl+IF+AymvJuhbj4xUIYlDfUS2HIUTHRc+COiz8RxL0+njfo6mn arturo@arturo-ThinkPad-L440

This keypair can authenticate an user which connects via SSH.

Installing the public key on Junos

We already know that a basic authentication schema on Junos looks like this.

admin> show configuration system login 
user admin {
    uid 2000;
    class super-user;
    authentication {
        encrypted-password "$1$kYNQ.bg0$4T3W7GAPuXwsX3nbbsRCb/"; ## SECRET-DATA

The main idea of using SSH keys, is to avoid user interaction, by trusting the keys instead of a credentials combination.

As seen above, the keys are plain text files. We need to install the public key on the Junos configuration, either configuring it manually, or using Ansible to configure it.

Manually configuring the key

I added a new user called ansible, set its class as super-user and configured its authentication as ssh-rsa.

admin# show system login | display set                                                                                                                                 
set system login user admin uid 2000
set system login user admin class super-user
set system login user admin authentication encrypted-password "$1$MExZQJdK$lLhnzSw.CLSMQg5bdIiws."
set system login user ansible uid 2001
set system login user ansible class super-user
set system login user ansible authentication ssh-rsa "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCfRe11M8nFYdAd5aLwjBI4a2yBbBbfPzpn3V50fR0FLpJYPOax5ayFJMPY90PwRTSYZpzVX36tYglgjDRVmWlN4QqI2dL7X994fGWf5LQsvCf3UTp+BVG3qQT/25O/bXs9rl4/kcts+5LA+xUzBGB0IkvWlggVqAkvKuxqQNYTSoO0FdnR96d2ZSvo2usIuh+McGREBK+In0ThW/Hhiqsb1qT7aNfbWDQtE3Fn+cW/a4fBV4iCJsL7UmJn8gZoFI0Ki8XXfXBvUBTIublnkM28zqG7YLr5wxM01Dl+IF+AymvJuhbj4xUIYlDfUS2HIUTHRc+COiz8RxL0+njfo6mn arturo@arturo-ThinkPad-L440"

The SSH public key is copied and pasted between double quotes.

Using Ansible to configure the key

Altough the key can be configured manually on the remote hosts, what if we have hundreds, or thousands of hosts to configure?

The idea behind this series of posts is to use Ansible whenever possible, so, let’s write a quick playbook to automate the key configuration.

rturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ cat junos-install-ssh-key.yaml 
- hosts: all
  gather_facts: no

    - auth_key: "{{lookup('file', '{{ key_file }}')}}"    

    - name: Install SSH key on remote host
          - set system login user ansible authentication ssh-rsa "{{ auth_key }}"
          - set system login user ansible class super-user

The playbook starts as usual, matching all hosts in the inventory, and without gathering facts, just for the sake of speed.

On vars, we are using the lookup plugin to read from a file and store its contents on a variable. Lookup can retrieve data from multiple sources, for example, take a secret from Hashicorp’s Vault. In this scenario, it will read a file which name is take from the key_file variable from the inventory.

It is possible to set a fixed file name on the playbook, but by taking the filename as a variable from the inventory, it gives us more flexibility. We could have multiple keys and rotate them by just changing the file name on the inventory, or use different keys per host group, and still apply the playbook to the full inventory, while using the proper key for each group.

The inventory for this playbook looks like the following. Notice the key_file variable which tells the playbook where to look for the key.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ cat junos-hosts.yaml 
      ansible_connection: netconf
      ansible_network_os: junos
      ansible_user: admin
      ansible_password: Password$1
      key_file: juniper-hosts.key.pub

Running the playbook to install the key

The current configuration of router logins is:

admin> show configuration system login 
user admin {
    uid 2000;
    class super-user;
    authentication {
        encrypted-password "$1$MExZQJdK$lLhnzSw.CLSMQg5bdIiws."; ## SECRET-DATA

Let’s run the playbook to apply the new configuration which will create the ansible user, set ssh-rsa authentication for it, and set its class as super-user.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ansible-playbook junos-install-ssh-key.yaml -i junos-hosts.yaml 

PLAY [all] *****************************************************************************

TASK [Install SSH key on remote host] **************************************************
changed: []

PLAY RECAP *****************************************************************************            : ok=1    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0 

Ok, the playbook executed with no errors, and Ansible says there is 1 changed host, which is what we expected.

Let’s check the router configuration again.

admin> show configuration system login    
user admin {
    uid 2000;
    class super-user;
    authentication {
        encrypted-password "$1$MExZQJdK$lLhnzSw.CLSMQg5bdIiws."; ## SECRET-DATA
user ansible {
    uid 2001;
    class super-user;
    authentication {
        ssh-rsa "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCfRe11M8nFYdAd5aLwjBI4a2yBbBbfPzpn3V50fR0FLpJYPOax5ayFJMPY90PwRTSYZpzVX36tYglgjDRVmWlN4QqI2dL7X994fGWf5LQsvCf3UTp+BVG3qQT/25O/bXs9rl4/kcts+5LA+xUzBGB0IkvWlggVqAkvKuxqQNYTSoO0FdnR96d2ZSvo2usIuh+McGREBK+In0ThW/Hhiqsb1qT7aNfbWDQtE3Fn+cW/a4fBV4iCJsL7UmJn8gZoFI0Ki8XXfXBvUBTIublnkM28zqG7YLr5wxM01Dl+IF+AymvJuhbj4xUIYlDfUS2HIUTHRc+COiz8RxL0+njfo6mn arturo@arturo-ThinkPad-L440"; ## SECRET-DATA

There is a new user called ansible, with all the parameters we specified. That’s great!

Authenticating using keys

I wrote another playbook to show the system uptime

- hosts: all
  gather_facts: no

    - name: Get uptime
            - show system uptime
      register: uptime
    - name: Show uptime
      debug: var=uptime

And our inventory now looks like this.

      ansible_connection: netconf
      ansible_network_os: junos
      ansible_user: ansible
      ansible_ssh_private_key_file: juniper-hosts.key
      ansible_python_interpreter: auto_silent

There is no plain text password, but instead, by setting up the ansible_ssh_private_key_file variable, we are instructing Ansible to authenticate using the private key.

arturo@arturo-ThinkPad-L440:~/Desktop/ansible-01$ ansible-playbook junos-auth-with-key.yaml -i junos-hosts-w-key.yaml 

PLAY [all] *****************************************************************************

TASK [Get uptime] **********************************************************************
ok: []

TASK [Show uptime] *********************************************************************
ok: [] => {
    "uptime": {
        "ansible_facts": {
            "discovered_interpreter_python": "/usr/bin/python"
        "changed": false, 
        "failed": false, 
        "stdout": [
            "Current time: 2020-01-12 16:25:10 UTC\nSystem booted: 2020-01-12 13:42:06 UTC (02:43:04 ago)\nProtocols started: 2020-01-12 13:42:27 UTC (02:42:43 ago)\nLast configured: 2020-01-12 16:09:02 UTC (00:16:08 ago) by admin\n 4:25PM  up 2:43, 3 users, load averages: 0.08, 0.02, 0.01"
        "stdout_lines": [
                "Current time: 2020-01-12 16:25:10 UTC", 
                "System booted: 2020-01-12 13:42:06 UTC (02:43:04 ago)", 
                "Protocols started: 2020-01-12 13:42:27 UTC (02:42:43 ago)", 
                "Last configured: 2020-01-12 16:09:02 UTC (00:16:08 ago) by admin", 
                " 4:25PM  up 2:43, 3 users, load averages: 0.08, 0.02, 0.01"

PLAY RECAP *****************************************************************************            : ok=2    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0 

This is great, now Ansible authenticates using the SSH key. You maybe are thinking:

“Do i have to edit my inventory every time i want to use keys?”

The answer is, no, and in the next post we will set a interactive prompt to connect using user and password to run the first playbook, which will configure the key, and then we will run all the other playbooks connecting with this key.

Stay tuned for more!

Contributing to Netbox devices library

The Netbox community has launched a repository for standard devices.


This comes handy for new and existing Netbox installations, because now you can populate your database with predefined device models for the most common networking gear manufacturers.

I have contributed to the repository and created the entire set of MikroTik routers and switches, updated to December 2019.


Feel free to use it and contribute!
And as always, you can find me on Github at https://github.com/baldoarturo