The speed of the resync depends on how you configured it. I seem to remember you saying that the network was OK. This was actually why I asked you in the beginning if you were using protocol C, since low I/O on the primary node would be a result of a problem with write performance on the second node, being it because of a problem with the local storage there or with the DRBD link.
Anyways, good that you have it solved now. On to the next problem ;-) On 02/19/11 01:10, Robinson, Eric wrote: > Mystery appears to be solved! > > The Ethernet card being used for DRBD replication was flaky in the old > secondary. Apparently replication was sometimes going super slow. That > explains why BOTH nodes had the high iowait problem when they were > primary, but NEITHER had high iowait when they were secondary. We're > using Protocol C, so processes on the primary kept queuing up waiting > for io calls to complete because DRBD could not write them to the other > node fast enough. > > It also explains my other question about the resync continually > stalling. Seriously, did NOBODY in the list notice when I said the > resync was going at a max of about 80K? When the NIC issue was resolved, > resyncs now happen at 30,000K. :-) > > I discovered the problem when I rebooted the server again and it said > "PCIe training error, slot3" and the system halted. You guessed it, slot > 3 was the NIC doing the replication. I reseated the card and it came up > fine and now replication is fast and I do not expect any more iowaits. > Next task... Replace that NIC. > > Thanks for everyone's help and suggestions. > > -- > Eric Robinson > > > > > > > > Disclaimer - February 18, 2011 > This email and any files transmitted with it are confidential and intended > solely for [email protected]. If you are not the named addressee you > should not disseminate, distribute, copy or alter this email. Any views or > opinions presented in this email are solely those of the author and might not > represent those of Physicians' Managed Care or Physician Select Management. > Warning: Although Physicians' Managed Care or Physician Select Management has > taken reasonable precautions to ensure no viruses are present in this email, > the company cannot accept responsibility for any loss or damage arising from > the use of this email or attachments. > This disclaimer was added by Policy Patrol: http://www.policypatrol.com/ > _______________________________________________ > drbd-user mailing list > [email protected] > http://lists.linbit.com/mailman/listinfo/drbd-user _______________________________________________ drbd-user mailing list [email protected] http://lists.linbit.com/mailman/listinfo/drbd-user
