Slow Synchronization

[andymack]

After having to take down both nodes to upgrade to 5.4, I was hoping that the re-sync procedure for a mirrored pair of servers would be much faster. Unfortunately this still doesn't seem to be the case. In our situation we are looking at a re-sync rate of about 1 TB/day. On the bright side, the speed seems reasonably consistant regardless if we re-sync a single empty LUN with no data (other than a VMFS file system) or a 50% full LUN. Still overall, I won't see the two nodes synced for at least 48 hours.

Speeds between servers are amazing, I can easily saturate 1 Gbps for over an hour when running a file transfer between the two servers. So why can't the sync saturate the connection (not to mention there are currently 4 active NIC's on the server)? Anyone else see this issue as well?

[mooseracing]

Have you scrolled down and seen the multipage Slow HA Sync thread?

Might be some usefull info in there for you. I'm in the same boat, but my sync partner only has 1Gb connection, whereas my main HA box and Hyper V servers have 10Gb.

[anton (staff)]

Apply for Beta program and get hands over V5.5 as it has sync speed doubled and has now fast sync enabled for Write-Back Cache configuration.