Reset admin password on UniFi controller to access wireless configuration.
Install whois package to use overfeatured front end to crypt(3).
$ sudo apt-get install whois
Generate new password using random salt.
$ printf "mypassword" | mkpasswd --stdin --method=sha-512 $6$LvF7R7Q3qo$bXFAWhbscrQ1rxYXF.Ut.iJ5I.59HBx8mpJnF3AayklAgX/izmh/Q16jG4aSlbI557QbwxnnV8LfkyqC0cZhc/
Use ssh to access remote machine.
$ ssh unifi.example.org
Connect to the local MongoDB instance.
$ mongo --port 27117 --shell --quiet
List databases.
> show dbs ace 0.001GB ace_stat 0.000GB local 0.000GB
Switch the current database to ace.
> use ace switched to db ace
List admins.
> db.admin.find()
{ "_id" : ObjectId("5a4552a24f0c66c01a730277"), "x_shadow" : "$6$IeSrq0LS$14mN.UZ5yh2wXspXr.Ee6flD5vg5wRmMqgmnX9DL79u2o/9Z9EaBkLx2Di8OG.Gb0wq6Vy4wnEpg.7Istdfuu1", "name" : "root", "email" : "milosz@sleeplessbeastie.eu", "time_created" : NumberLong(1514492578), "last_site_name" : "default" }
Replace value of the x_shadow field with the previously generated password.
> db.admin.update({"_id":ObjectId("5a4552a24f0c66c01a730277")},{$set: {"x_shadow" : "$6$LvF7R7Q3qo$bXFAWhbscrQ1rxYXF.Ut.iJ5I.59HBx8mpJnF3AayklAgX/izmh/Q16jG4aSlbI557QbwxnnV8LfkyqC0cZhc/"}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 0 })
Verify that by some mistake you have not replaced whole document.
> db.admin.find({"name":"root"})
{ "_id" : ObjectId("5a4552a24f0c66c01a730277"), "x_shadow" : "$6$LvF7R7Q3qo$bXFAWhbscrQ1rxYXF.Ut.iJ5I.59HBx8mpJnF3AayklAgX/izmh/Q16jG4aSlbI557QbwxnnV8LfkyqC0cZhc/", "name" : "root", "email" : "milosz@sleeplessbeastie.eu", "time_created" : NumberLong(1514492578), "last_site_name" : "default" }
Use new password to access UniFi controller.