Running tcpdump on Ubiquiti Airmax Equipment

Ubiquiti Airmax gear has tcpdump included. We can easily use it to capture packets to a file and then use SCP from the device to copy the file for analysis.

SSH to the device

ssh ubnt@192.168.1.20
cd /tmp/

Start tcpdump with the following command. Change ath0 and file.cap to the appropriate interface and file name.

tcpdump -i ath0 -w file.cap

After we are done collecting, we can quit with ctrl + c

Now we can use scp or sftp to copy the files off. There is an issue using scp or sftp from a normal Linux machine to the radio, fails with a “sh: /usr/libexec/sftp-server: not found”. It works fine if you initiate scp from the radio.

scp /tmp/file.cap username@remoteip:~/

Find UniFi Network Cloud Inform URL

What is the format for the UniFi Network Cloud inform URL?

The format for the UniFi inform URL should be similar to the following

a38927b1-23aa-e95d-94b4-8394abce9302.unifi-hosting.ui.com

Now Where is the UniFi Cloud Inform Link?

The inform URL is supposed to be on the cloud console page. However, it appears that it doesn’t show the link if you are not Owner.

Web Development Tools to the rescue!

On the UniFi console page, click on “About this Console”

Open up the Web Tools, Click on the Network tab, make sure that you have the Domain column enabled.

Refresh the page.

Look for the Domain that matches the UniFi Cloud URL format.

Example: a38927b1-23aa-e95d-94b4-8394abce9302.unifi-hosting.ui.com

You can confirm this is the correct URL by browsing to it directly. It should redirect to your cloud instance.

Extra tip: If you are migrating from a UniFi Console (CloudKey, UDM, DreamMachine) to UniFi Cloud, you can restore a backup of your CloudKey (Or other console) and then use the Host Inform Override option (from CloudKey) to tell all the devices on the network to connect to the cloud instance. May need to reboot or force provision.

https://community.ui.com/questions/Unifi-Controller-Migration-Question/a49914df-f770-4c2d-a0e4-143d6314c9a4

Change VLAN ID Ubiquiti Radio from SSH

First we’ll need to ssh into the device

ssh ubnt@192.168.1.20

Next lets open up the config file

vi /tmp/system.cfg

Now search for vlan and replace the vlan id with the appropriate number

In VI you can search by hitting / and then type in vlan

After you have changed all the vlan ids, save the file with esc, wq, enter.

Now we can save the config with

cfgmtd -f /tmp/system.cfg -w && reboot

Disable Wireless Security (WPA2) Preshared Key on Ubiquiti AC

Update: Found this handy dandy FAQs link https://help.ui.com/hc/en-us/articles/115009192828

Included in the FAQ is a section on “How to Disable Wireless Security on airMAX AC Devices?”

The default security configuration for AC devices since firmware version 8.5.11 was changed to WPA2 AES with a pre-shared key 0000:0000.

Ubiquiti Default AC device WPA2 Preshared key

On Ubiquiti AC radios, you can not disable WPA 2 security through the web interface. This is not necessarily bad, however, what happens if you have a client that is reset and will only connect to the default ubnt SSID?

Fortunately there is a way to disable the WPA2 Preshared key.

  1. Log into the device over ssh.
  2. Run the following command to disable WPA2 in the config
    sed -i s/aaa.1.wpa.mode=2/aaa.1.wpa.mode=0/g /tmp/system.cfg
  3. Save the config file with
    /usr/etc/rc.d/rc.softrestart save
  4. Login to the client device and configure the SSID.

After you are done, you can click the enable button to re-enable Wireless Security.

Screenshot from UI help page on Wireless Security on airMAX AC devices

Searching for devices in UniFi via command line / MongoDB

While the UniFi controller is nice and everything, it does make it hard to see if a device is already adopted. At least if you have a ton of sites. Fortunately, we can search the database directly to find out if a UniFi is already adopted and which site it is assigned to.

Connect to Mongo DB

First we need to connect to MongoDB. And then we need to use the ace database.

mongo -port 27117
use ace

List all the devices on the controller

This command will list all the devices on the controller. Regardless of which site they are assigned to.

db.device.find({}, { site_id:"", ip : "", name :"", mac:""})

Example output

{ "_id" : ObjectId("563a4d94e4b054e5376fc600"), "mac" : { "_id" : ObjectId("563a4d94e4b054e5376fc600"), "mac" : "44:d9:e7:34:d1:08", "ip" : "192.168.1.200", "name" : "Main_WiFi", "site_id" : "39485e9abf0e9a047bcded96" }
{ "_id" : ObjectId("9873b39ed1f5d30a6738abe"), "mac" : "44:d9:e7:01:a3:d4", "ip" : "192.168.1.201", "name" : "Testing_Wifi", "site_id" : "39485e9abf0e9a047bcded96" }

Each UniFi will have a “site_id”. You can use that ID to figure out which site it is assigned to.

List all the sites on the controller

db.site.find()

Example output

{ "_id" : ObjectId("39485e9abf0e9a047bcded96"), "name" : "default", "desc" : "Testing Site", "attr_hidden_id" : "default", "attr_no_delete" : true, "anonymous_id" : "83ae20ba-2948-458e-fd0a-1320583ecb04" }

Using our “site_id” from above, we see that the Testing_Wifi device is assigned to the “Testing Site” on the controller.

Something else to look at would be to use the UniFi controller API.

https://ubntwiki.com/products/software/unifi-controller/api

Change UniFi User Password from Command Line

  1. SSH into the UniFi server
  2. Connect to MongoDB
  3. Find user ObjectId
  4. Update user info with new Password

You will need a hash of the password to put into the database. We don’t cover that in this post. You could copy the password from a different user account or use a different UniFi instance to change the password and then check the DB to find the hash.

SSH into the UniFi Server

ssh unifiadmin@unifiserver

Connect to MongoDB

Connect to Mongo by typing in the following.

mongo -port 27117

Then select the ace database by typing

use ace

Find user ObjectId

The admins are in the admin collection/table. Use the following command to list all the users and their name, email, and password hash.

db.admin.find({ }, { name:"" , email : "", "x_shadow" : "" })

Update user info with new Password

The following looks complex. Fortunately though you should be able to copy and paste. You should only need to change the
– ObjectId to your User Id
– Password Hash to your password hash

db.admin.update({"_id" : ObjectId("223abc5489de0a93be758493")}, {$set: { "x_shadow" : "$6$nwpi7.q2$OuD9/UZGZt5cD739Dt7j8Gb1uPtfU99p0DeDSurSNBZVizieUrFVFbRufiZMgOk2IaaDZN9BVmL9yUwQ2mC8f."}});

Note: The hash above is password. Not recommended for use.

You should receive a confirmation that it succeeded. Test the new password by logging into the UniFi Controller.

For more MongoDB commands, check out this post.

UniFi-Video Service failing to Start

Do note that the UniFi-Video software is no longer supported should be migrated to the UniFi Protect systems.

Running “systemctl status unifi-video” gives the following error.

(unifi-video) checking for system.properties and truststore files…
…fail!

It appears that the error is due to an unsupported version of Java. Installing an older version of Java resolves the issue.

You can check which versions of Java are available with

apt-cache show openjdk-8-jre

The versions that showed up for me were

8u282-b08-0ubuntu1
8u252-b09-1ubuntu1 

Installing the last one fixed the issue for now.

sudo apt-get install openjdk-8-jre-headless=8u252-b09-1ubuntu1

https://old.reddit.com/r/Ubiquiti/comments/l30jm5/unifi_video_31013_not_compatible_with_openjdk_180/

Unable to Remove Authorized SSH Keys from AirOS

For some reason I ran into an issue where I can not remove authorized SSH Keys in AirOS version 6.3. It redirects to a 404 page and then to the main page.

Attempting to remove SSH keys in AirOS
404 Error while attempting to remove SSH keys

Thankfully, we can still remove the authorized keys from the command line. For more information on making changes over SSH, refer to the following post.

SSH into radio. Replace username and IP address with your radios user and IP.

ssh ubnt@192.168.1.20

Open up config file

vi /tmp/system.cfg

Search for the lines that contain

the sshd.auth.key and remove them

Remove the sshd.auth.key lines

Save the file and write the configuration with

/usr/etc/rc.d/rc.softrestart save

Once the command completes, you should be good to go.

Ubiquiti U Installer Screenshots and Configuration Interface

By default the U Installer redirects you to a page asking you to download the app. You can get to the actual U Installer web page by going to https://169.254.169.169

Default U Installer Page
Access U Installer Certificate Error

It has the same interface as a regular Airmax M equipment.

U Installer main page

Notes on Migrating UniFi-Video NVR Disk

Recently upgraded a UniFi-Video VM by creating a new VM and restoring the backup from the previous one. There was a separate virtual disk used for storing all the videos. Although once I reattached it, I had to change the owner to the unifi-video user. lt was reporting that the owner/group was 127 and 134, looks like that was the user ID from the previous VM.

Example output from ls -hla command

drwxr-xr-x 3 127 134 4.0K Jan 16 2020 176de761-8399-3bed-8ceb-917cbe4d25bd
drwxr-xr-x 2 127 134 4.0K Sep 10 12:28 21d506ef-dded-31f2-baf8-c109a7e653b9
drwxr-xr-x 4 127 134 4.0K Jan 1 2020 1a3afc4c-a030-39a1-b139-857444c8b71c

Ended up changing the owner to the unifi-video owner with the chown command. /path/to/videos is the mount point of the video drive.

chown -R unifi-video:unifi-video /path/to/videos