Upgrading your LA portal

Strategies to upgrade a LA portal

In general there are two main strategies to migrate your LA services and servers:

1. To install new servers and services from scratch using new versions of everything (like the OS), redeploy with ansible & ala-install and restore dbs and /data from backups or rsync or similar. In general the philosophy of devops (and ansible and ala-install) is to not touch servers manually, so if you have a good LA inventory (these generated by the la-toolkit, for instance) and you didn't install or configured nothing manually, it's quite easy to reproduce and restore servers and services or upgrade them. You'll need extra servers, and it's quite safe because you don't switch to production the new servers until you are sure that are working. For this you can play with your hosts file to verify the upgrade of the services and later to switch to use them in production via a real DNS change.
2. To upgrade using the same servers. This is more risky, but sometimes easy, when you are doing small version upgrades. You can also do OS upgrades that way, but the same, it's more risky as you are upgrading production servers.

In general with option 1) you play with /etc/hosts, or DNS and/or proxies until you are sure that the updated service is working and you change the DNS/proxies to put that new servers in production.

In which order we need to upgrade a LA Portal?

We don't have an unique order to upgrade modules, but there are some LA modules that are more easy to upgrade than others.

So you can try to upgrade LA services that do not have a db backend theyself, like regions or bioacache-hub, bie-hub, biocache-service... These are more safe to migrate or test and to downgrade if you detect some issue.

Also sometimes you have to migrate some services to maintain compatibilities and dependencies.

Keeping your /data/ configs well configured

If you managed your /data/*/config manually for some reason instead of using ansible and you want to use ala-install instead, you have to create a correct ansible inventory with all these manual /data/ configurations translated into the corresponding ansible variables. The la-toolkit can help you to get an initial version of your inventories, update your config and see the differences. For this is good to keep track of you configurations. We tried to describe this (and other related recommendations) here.

Cassandra

Schemas migration

From time to time our cassandra schema changes. We can use ALTER TABLE statements to update it, however the biocache-store detects missing fields and adds them automatically.

Migration notes

• image-service migration
• logger-service migration
• cas service upgrade notes

And remember

Backup, backup, backup