cywang117

1. Trigger an update with deltas enabled between release A and release B on a test device.
2. Find the delta image that gets pulled from balena images -- it should be REGISTRY_URL:DELTA_TAG
   • Alternatively, if running Supervisor v12.9.5 or greater (12.9.6 highly recommended), look in the Supervisor's journal logs.
   • Alternatively, make a request the delta endpoint with curl -H "Bearer: Authorization $(cat /mnt/boot/config.json | jq -r '.deviceApiKey)" "https://delta.balena-cloud.com/api/v3/delta?src=SOURCE_REGISTRY_URL&dest=TARGET_REGISTRY_URL". This should return the delta URL and is the best amongst these 3 alternatives, but from my own investigations and limited knowledge, this works sporadically so is not recommended.
3. After you have the registry delta URL, on production devices:
   • balena login registry2.balena-cloud.com -u d_$(cat /mnt/boot/config.json | jq -r '.uuid') -p $(cat /mnt/boot/config.json | jq -r '.deviceApiKey')
   • balena pull DELTA_URL
   • `balena image tag DELTA_URL

AmazingTurtle

Restore access to a unifi controller

When you are unable to login to the unifi controller or forgot admin password, you can restore access using SSH and manipulating mongodb directly.

Warning

Do not uninstall unifi controller - most of the data is not stored in mongodb. In case you thought a mongodb backup would be sufficient, you may have fucked up already, just like me. However I managed to write this "tutorial" for anyone to not run into the same trap.

Apparently this guide no longer works with recent unifi controller versions (starting nov/dec 2022). Since I no longer use unifi hardware in my home system, I can not update the guide myself. In case you've gotten here to recover your data, you're likely doomed. But giving it a try won't hurt anyway, therefore: good luck.

milesbxf

###################################################
##
## Alertmanager YAML configuration for routing.
##
## Will route alerts with a code_owner label to the slack-code-owners receiver 
## configured above, but will continue processing them to send to both a
## central Slack channel (slack-monitoring) and PagerDuty receivers
## (pd-warning and pd-critical)
##

rgreenjr

-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'