Hi guys, I'll be performing a migration on my production master database server, which is running PostgreSQL 9.2 atm, from SATA disks to SSD disks. I've got some questions about it, and it would be nice if u guys could share your experiences/thoughts:
*SCENARIO:* I currently have one MASTER and two Streaming Replication Slaves servers... master01 > slave01 (Streaming replication + wal_files) > slave02 (Streaming replication + wal_files) ...Postgres is mounted on: /var/lib/pgsql/... The SSD disks will be installed only on my Master server, because my main problem is Writes and not reads. The new SSD volume will be mounted on /var/lib/pgsql2/ - The slave02 server will loose the streaming replication connection to the master, once slave01 becomes the new master a new timeline will be settled? Will slave02 be able to connect to the slave01 server for streaming replication? *MIGRATION OPTIONS:* *Migration Option 1:* *I know this option will work* 1. Mount the new volume */var/lib/pgsql2/ *on the master01 server 2. Turn slave01 into a master server 3. once I can confirm everything is working fine, I can go to step 4 4. Stop postgres on the master01, start copying the DB using pg_basebackup from slave02 to master01 (Will have to edit postgres to use /var/lib/pgsql2/ instead /var/lib/pgsql - Is that possible? Or I'd have to create a symbolic link?) 5. Start postgres on master01 server and check if all goes well as streaming replication server (Will test it for days) 6. Turn master01 into a master server and I'll have to re-copy the DB into slave01 to make it a streaming replication server again *Migration Option 2:* *I don't know if this is possible - IS THIS POSSIBLE????* 1. Mount the new volume */var/lib/pgsql2/* on the master01 server 2. Stop postgres on the server (I won't stop postgres on the slave so the users will be able to use the server as read-only) 3. Copy the data from /var/lib/pgsql/ to /var/lib/pgsql2/ 4. Configure postgres to start using the new volume(/var/lib/pgsql2/) What do you guys think? Is option possible? if so it would be much easier :) Thanks!
