Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
The Initiators I use are: VMWare ESX 3.0.x, VMWare ESX 3.5.x, Micrsoft iSCSI Initiator 2.08, and Linux (RHEL 5, SUSE 10). I gave SQLIO a run with your params and I'm not getting the concurrent write issue. The hardware I run DRBD is a pair of HP Proliant DL380 G4 servers with 12GB of RAM and P600 SAS controllers. The machines are currently replicating 1.8TB of data. I run DRBD under SuSE 10SP2 and use IET stock from SuSE but the DRBD is 8.0.16. - Morey Roof Information Services Department New Mexico Institute of Mining and Technology ________________________________ From: drbd-user-bounces at lists.linbit.com [mailto:drbd-user-bounces at lists.linbit.com] On Behalf Of Gennadiy Nerubayev Sent: Tuesday, April 21, 2009 3:18 PM To: drbd-user at lists.linbit.com Subject: Re: [DRBD-user] Concurrent writes On Tue, Apr 21, 2009 at 2:47 PM, Roof, Morey R. <MRoof at admin.nmt.edu> wrote: This is a really interesting discussion. I use DRBD to replicate volumes that are exported via blockio with IET and have never gotten this message. I currently use DRBD 8.0.16 and over the last year with 8.0.x series this message has never appeared. Before deployment all sorts of io tests were conducted and this message wasn't present then either. Thanks for the input. What are the initiators that you're using? So, I have an idea of a setting for you to change on your iSCSI target system and I'm really curious if the message goes away. In IET we have "InitialR2T Yes" but the default is "No". Trying running that way and see what happens as I'm very curious about the results. Just tried "InitialR2T Yes", and there was no effect; the concurrent write warnings are still being generated. As a side note for anyone who would like to test this, on windows in particular, here's one of tools I use to duplicate this: SQLIO: http://www.microsoft.com/downloads/details.aspx?familyid=9a8b005b-84e4-4 f24-8d65-cb53442d9e19&displaylang=en Contents of param.txt (this assumes f: is the remote storage, and you have one gb free space available): f:\testfile.dat 4 0x0 1024 Command to run: sqlio -kW -s60 -frandom -o8 -b8 -LS -Fparam.txt -Gennadiy