Yes, I've about come to the conclusion that multipath will not work with a drbd resource, and Oracle VM will not work with a non-multipath resource. So, no DRBD > LVM > Multipath > Oracle VM either. Dang!
Of course multipath will work with the underlying device, but then drbd cannot replicate it except offline and without benefit of the activity log or bitmap. Close to useless. Looking like a second server (or SAN) is going to be required to run any sort of DR other than occasional [incremental] backups managed manually. Sigh, ... -----Original Message----- From: Pascal BERTON [mailto:[email protected]] Sent: Tuesday, April 10, 2012 3:30 PM To: 'Dan Barker'; 'drbd List' Subject: RE: [DRBD-user] multipathd ignores my drbd0 Dan, Isn't it the backing device you should refer ? To me, if you want multipath to work correctly, the device has to return an ID. Having said that, if I try it on my resource having the following config file : resource vmfs2 { device /dev/drbd1; disk /dev/vg_vmfs2/lv_vmfs2; meta-disk internal; net { } disk { } on ipstore11 { address 195.165.5.245:7791; } on ipstore21 { address 195.165.5.247:7791; } } If I try : [root@ipstore21 ~]# scsi_id --whitelisted --device=/dev/vg_vmfs2/lv_vmfs2 3600508b1001c3a60557b6713c82b915c [root@ipstore21 ~]# Now, if I try : [root@ipstore21 ~]# scsi_id --whitelisted --device=/dev/drbd1 [root@ipstore21 ~]# As far as I understand, if no SCSI ID, multipathd can't identify the device, so no multipath... But configuring it with the backing device should work... HTH. Regards, Pascal. -----Message d'origine----- De : [email protected] [mailto:[email protected]] De la part de Dan Barker Envoyé : mardi 10 avril 2012 21:08 À : 'drbd List' Objet : Re: [DRBD-user] multipathd ignores my drbd0 Yes. In fact I had a bit of bother to get multipath not to grab my DRBD resources. The multipath.conf blacklist regexps didn't seem to work the way I expected. I resorted to putting the scsi-id names in blacklisted.wwids. Of course, that may mean that the drbd resource was blacklisted, but multipath -ll -v3 has zero occurrences of "drbd" in it. Dan -----Original Message----- From: Kushnir, Michael (NIH/NLM/LHC) [C] [mailto:[email protected]] Sent: Tuesday, April 10, 2012 1:23 PM To: Dan Barker; 'drbd List' Subject: RE: [DRBD-user] multipathd ignores my drbd0 Did you check multipath blacklists? -Michael -----Original Message----- From: Dan Barker [mailto:[email protected]] Sent: Tuesday, April 10, 2012 12:40 PM To: 'drbd List' Subject: Re: [DRBD-user] multipathd ignores my drbd0 I've tried everything I can think of to get mapper to pick up the drbd0 device, and all failed. I put in a symlink (ln -s /dev/drbd0 /dev/mapper/DRBD0) but Oracle VM doesn't see it. I'm guessing it's requiring multipath to access the resource. I'll try some Logical Volumes and see if I can make Oracle VM see those. I know I can build a PV/VG/LV from a drbd resource. Running an iSCSI target and initiator on localhost on this machine is getting a bit too weird, even for Oracle<g>. Thanks for the tips! Dan -----Original Message----- From: Kaloyan Kovachev [mailto:[email protected]] Sent: Tuesday, April 10, 2012 9:53 AM To: Dan Barker Cc: drbd List Subject: Re: [DRBD-user] multipathd ignores my drbd0 I think you can't use DRBD device directly with multipath, but if you export it via iSCSI and then import it back it is possible. Another option is LVM over DRBD -> device in /dev/mapper Another one is just a symlink in /dev/mapper from udev rule On Tue, 10 Apr 2012 09:41:13 -0400, "Dan Barker" <[email protected]> wrote: > How do I get multipathd to notice my drbd block devices? > > RHEL5 (Oracle VM 3.0.3.127, actually), 2.6.32.21-45xen. > Drbd 8.4.1: > multipath-tools says v0.4.9. I can't seem to find the multipath version. > > resource r0 { > on OVMPam { > volume 0 { > device /dev/drbd0 minor 0; > disk /dev/sdb; > meta-disk internal; > } > address ipv4 172.30.0.167:7789; > } > on DRPam { > volume 0 { > device /dev/drbd0 minor 0; > disk /dev/sdb; > meta-disk internal; > } > address ipv4 172.30.0.170:7789; > } > startup { > become-primary-on OVMPam; > } > } > > As-distributed global. > > All multipath commands reply "Apr 09 08:10:50 | DM multipath kernel driver > not loaded", as if no devices were detected at boot time. > > I have drbd start before multipathd. > > Relax, I have no plans to multipath to this device, Oracle VM looks > only in > /dev/mapper for repository candidates. > > New 10 April: Ping! Anyone have any ideas? Even a different forum in which > to ask? > > _______________________________________________ > 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 _______________________________________________ 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
