On 31 Mar 2014, at 13:59, Dan Barker <[email protected]> wrote:
>> -----Original Message----- >> From: [email protected] [mailto:drbd-user- >> [email protected]] On Behalf Of Bart Coninckx >> Sent: Monday, March 31, 2014 6:51 AM >> To: Arnold Krille >> Cc: [email protected] >> Subject: Re: [DRBD-user] Single versus multiple DRBD devices >> >> >> On 28 Mar 2014, at 22:04, Arnold Krille <[email protected]> wrote: >> >>> On Fri, 28 Mar 2014 10:40:28 +0100 Bart Coninckx >>> <[email protected]> wrote: >>>> All, >>>> >>>> >>>> building a storage cluster which will offer SCST targets. These will >>>> be LVM based (nested LVM probably). In terms of performance, what is >>>> the most optimal strategy: one big DRBD device where the different >>>> Logical Volumes are installed on or a DRBD device per LV? If a resync >>>> needs to be done, the latter will probably better, as it allows us to >>>> choose which devices should be resynced first. >>> >>> I do have several drbd volumes instead of one big. Then you can >>> choose which ones to sync first. And if your volumes are on different >>> disks, the order can be defined to sync volumes from each disk one >>> after the other but volumes from different disks in parallel. That way >>> one can max out a 2x10G connection with three volumes from three disks >>> all reading/writing sequential, instead of the disk stepping in its own >>> way by reading from several volumes on the same disk while the other >>> disks are idle... >>> >>> And several drbd-volumes can fail-over individually. >>> >>> Have fun, >>> >>> Arnold >> >> >> Sounds reasonably! Thank you for your input! >> >> BC >> > > What Bart is suggesting is matching your drbd definition to your physical > environment. Your OP was about the logical environment. You'll probably have > a combination of factors drive your design. For example, I have four DRBD > resources servicing about 20 VMs. The four DRBD resources mirror my physical > environment and the VMs are spread around on these four devices to minimize > the impact of a failure or slow-down on any one. > > Dan > > _______________________________________________ > drbd-user mailing list > [email protected] > http://lists.linbit.com/mailman/listinfo/drbd-user Dan, what do you mean by "DRBD resources mirroring your physical environment"? Cheers, BC _______________________________________________ drbd-user mailing list [email protected] http://lists.linbit.com/mailman/listinfo/drbd-user
