Historically wikitech has been deployed as self-contained systems with a local MySQL/MariaDB database server co-located with the MediaWiki software. This was done in an attempt to maintain availability of the technical documentation on wikitech in the event of outages in other parts of the network.
Today, we are monitoring and responding to alerts about staleness on the off-site hosted wikitech-static server. The cloud-services-team is also moving forward with a long term plan to remove LDAP auth and OpenStackManager from wikitech so that it can become a normal SUL wiki. These changes mean that eventually wikitech will be hosted in the common MediaWiki wiki farm (T161859). We will rely on the offsite copy of documentation for severe outage support rather than maintaining a single point of failure machine and hoping that it is unaffected.
Moving the labswiki database from m5 to the s3 slice will benefit us with better maintenance, upgrades, monitoring and high availability. Making this move sooner rather than later will reduce the potential to lag behind in schema updates and cause issues with cross-wiki maintenance like we have seen in the past (e.g. T167961).
This could happen at the same time that other movements are being prepared
After the DC switch progress work: T167973#7232200
Migration and clean up progress work: T167973#7359504