Mentat

This should be postponed a bit. Debian package tracker lists PostgreSQL 11 as what I gather is not ready for upgrade due to dependency issues. I advise to test the upgrade manually on mentat-dev but right now it is busy with #4383 and interrupting this would make comparing gathering the results there harder (first I waited for this to be resolved but it seems to linger hence the other course as plotted above).

Everything seems to be working OK on mentat-dev after upgrade using the following (official) procedure:

$ sudo systemctl stop postgresql

$ sudo apt-get update

$ sudo apt-get install postgresql-11 postgresql-11-ip4r

$ sudo pg_lsclusters                                                                                                                                                                          
Ver Cluster Port Status Owner    Data directory              Log file
10  main    5432 online postgres /var/lib/postgresql/10/main /var/log/postgresql/postgresql-10-main.log
11  main    5433 online postgres /var/lib/postgresql/11/main /var/log/postgresql/postgresql-11-main.log

$ sudo systemctl stop postgresql

$ sudo pg_dropcluster 11 main

$ sudo pg_lsclusters
Ver Cluster Port Status Owner    Data directory              Log file
10  main    5432 down   postgres /var/lib/postgresql/10/main /var/log/postgresql/postgresql-10-main.log

$ sudo pg_upgradecluster --method=upgrade 10 main

$ sudo pg_dropcluster --stop 10 main

$ sudo apt-get remove --purge postgresql-10 postgresql-client-10

$ sudo systemctl start postgresql

psql:
VACUUM VERBOSE;
ANALYZE VERBOSE:

1. New comments and options are not added to the postgresql.conf (Oh how I miss the Slackware's diff and merge approach to config file upgrade);
2. What about the postgresql-server-dev-10 package? Any idea what it was used for? It does not seem to be required.

Debian devs are still trying to resolve some issues with llvm and/or postgresql-common update, neither is tremendously important to us.

I am happy with the outcome, requesting green light to go for mentat-alt (Downtime required).

Radko Krkoš wrote:

Everything seems to be working OK on mentat-dev after upgrade using the following (official) procedure:

[...]

Only outstanding issues are:

1. New comments and options are not added to the postgresql.conf (Oh how I miss the Slackware's diff and merge approach to config file upgrade);
2. What about the postgresql-server-dev-10 package? Any idea what it was used for? It does not seem to be required.

This is a requirement for compiling the python psycopg2 library. So sadly it needs to stay. Or to put it more correctly, the appropriate package for v11 needs to be installed as well.

Debian devs are still trying to resolve some issues with llvm and/or postgresql-common update, neither is tremendously important to us.

I am happy with the outcome, requesting green light to go for mentat-alt (Downtime required).

Perfect, but please wait until Wednesday 31. I will be at Prague premises on Monday and Tuesday and will need working environment to demonstrate current work in progress. But on Wednesday 31 you may proceed, outstanding work.

Jan Mach wrote:

Radko Krkoš wrote:

1. What about the postgresql-server-dev-10 package? Any idea what it was used for? It does not seem to be required.

This is a requirement for compiling the python psycopg2 library. So sadly it needs to stay. Or to put it more correctly, the appropriate package for v11 needs to be installed as well.

I expected some such thing. Good to know, I will fix mentat-dev and alter the procedure.

Perfect, but please wait until Wednesday 31. I will be at Prague premises on Monday and Tuesday and will need working environment to demonstrate current work in progress. But on Wednesday 31 you may proceed, outstanding work.

OK, postponing the upgrade on mentat-alt until next week.

Upgraded to PostgreSQL 11.1 on mentat-dev and mentat-alt. The update contained some security fixes which should not affect us much and also a set of other fixes, nothing too important. The developers recommended an ASAP update nevertheless, so we complied.
No change is required for the update procedure.

Radko Krkoš wrote:

The resulting procedure steps are as follows:

All as root:
[...]

This is for hands-on upgrade. For automated variant (Ansible?) the verification steps should be skipped.

How to perform the upgrade on mentat-hub? Ansible? Manual?

Hi Radko, I would like to plan the database upgrade on Friday the 16th of November, if that is OK with you. Also I would like to ask you to do it, because I do not want any hiccups on the production server. I think, that the downtime beginning on Friday morning will have the smallest possible impact on the users. Please reboot the whole server as mentioned in the upgrade checklist, so that the new kernel gets loaded and disks checked. Great work on this issue so far, thank you very much.

To Radko: I have just added your database update procedure checklist to the upgrade section of the documentation. I have created the commit with you as an author, so you can get the credit for coming up with that procedure. I have basically just pasted the checklist as you have created it to appropriate documentation file.