[solved] Python 3 upgrade seems to want redis and has broken our installation

We never had redis installed before and, after the upgrade it has started looking for redis and polling is no longer working. We always used the “new” poller, rather than the cronjob. validate.php is clean, but nothing is being logged to librenms.log and the gui complains about devices not being polled.

Blockquote====================================
Component | Version
--------- | -------
LibreNMS | 1.63-69-gf66b16932
DB Schema | 2020_04_13_150500_add_last_error_fields_to_bgp_peers (164)
PHP | 7.2.24-0ubuntu0.18.04.4
Python | 3.6.9
MySQL | 10.1.44-MariaDB-0ubuntu0.18.04.1
RRDTool | 1.7.0
SNMP | NET-SNMP 5.7.3
====================================

[OK] Composer Version: 1.10.6
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct

We are seeing lots of redis errors in syslog:

Blockquote
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: return self.parse_response(conn, command_name, **options)
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: File “/data/librenms/.local/lib/python3.6/site-packages/redis/client.py”, line 915, in parse_response
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: response = connection.read_response()
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: File “/data/librenms/.local/lib/python3.6/site-packages/redis/connection.py”, line 747, in read_response
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: raise response
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: redis.exceptions.ResponseError: unknown command ‘BZPOPMIN’
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: Services_0-17(ERROR):Services poller exception! unknown command ‘BZPOPMIN’
May 13 09:01:23 unix-mon02 librenms-service.py[5039]: Poller_0-26(ERROR):Poller poller exception! unknown command ‘BZPOPMIN’

If you are having troubles with discovery/polling include the pastebin output of:

./discovery.php -h HOSTNAME -d | ./pbin.sh
[pastebin](https://p.libren.ms/view/24624a40)
./poller.php -h HOSTNAME -r -f -d | ./pbin.sh
[pastebin](https://p.libren.ms/view/ade6d23b)

It seems that if redis is installed and running, librenms tries to use it. Either make sure it’s not running or make sure that all the components match what is in the requirements.txt. The version of python3-redis in Ubuntu 18.01 is not new enough…