Re: [ovirt-users] Recommended setup for a FC based storage domain

Interesting, which files did you modify to lower the log levels? On Tue, Jun 3, 2014 at 12:38 AM, <combuster(a)archlinux.us&gt; wrote: > One word of caution so far, when exporting any vm, the node that acts as SPM > is stressed out to the max. I releived the stress by a certain margin with > lowering libvirtd and vdsm log levels to WARNING. That shortened out the > export procedure by at least five times. But vdsm process on the SPM node is > still with high cpu usage so it's best that the SPM node should be left with a > decent CPU time amount to spare. Also, export of VM's with high vdisk capacity > and thin provisioning enabled (let's say 14GB used of 100GB defined) took > around 50min over a 10Gb ethernet interface to a 1Gb export NAS device that > was not stressed out at all by other processes. When I did that export with > debug log levels it took 5hrs :( > > So lowering log levels is a must in production enviroment. I've deleted the > lun that I exported on the storage (removed it first from ovirt) and for the > next weekend I am planing to add a new one, export it again on all the nodes > and start a few fresh vm installations. Things I'm going to look for are > partition alignment and running them from different nodes in the cluster at > the same time. I just hope that not all I/O is going to pass through the SPM, > this is the one thing that bothers me the most. > > I'll report back on these results next week, but if anyone has experience with > this kind of things or can point to some documentation would be great. > > On Monday, 2. June 2014. 18.51.52 you wrote: >> I'm curious to hear what other comments arise, as we're analyzing a >> production setup shortly. >> >> On Sun, Jun 1, 2014 at 10:11 PM, <combuster(a)archlinux.us&gt; wrote: >>> I need to scratch gluster off because setup is based on CentOS 6.5, so >>> essential prerequisites like qemu 1.3 and libvirt 1.0.1 are not met. >> Gluster would still work with EL6, afaik it just won't use libgfapi and >> instead use just a standard mount. >> >>> Any info regarding FC storage domain would be appreciated though. >>> >>> Thanks >>> >>> Ivan >>> >>> On Sunday, 1. June 2014. 11.44.33 combuster(a)archlinux.us wrote: >>>> Hi, >>>> >>>> I have a 4 node cluster setup and my storage options right now are a FC >>>> based storage, one partition per node on a local drive (~200GB each) and >>>> a >>>> NFS based NAS device. I want to setup export and ISO domain on the NAS >>>> and >>>> there are no issues or questions regarding those two. I wasn't aware of >>>> any >>>> other options at the time for utilizing a local storage (since this is a >>>> shared based datacenter) so I exported a directory from each partition >>>> via >>>> NFS and it works. But I am little in the dark with the following: >>>> >>>> 1. Are there any advantages for switching from NFS based local storage to >>>> a >>>> Gluster based domain with blocks for each partition. I guess it can be >>>> only >>>> performance wise but maybe I'm wrong. If there are advantages, are there >>>> any tips regarding xfs mount options etc ? >>>> >>>> 2. I've created a volume on the FC based storage and exported it to all >>>> of >>>> the nodes in the cluster on the storage itself. I've configured >>>> multipathing correctly and added an alias for the wwid of the LUN so I >>>> can >>>> distinct this one and any other future volumes more easily. At first I >>>> created a partition on it but since oVirt saw only the whole LUN as raw >>>> device I erased it before adding it as the FC master storage domain. I've >>>> imported a few VM's and point them to the FC storage domain. This setup >>>> works, but: >>>> >>>> - All of the nodes see a device with the alias for the wwid of the >>>> volume, >>>> but only the node wich is currently the SPM for the cluster can see >>>> logical >>>> volumes inside. Also when I setup the high availability for VM's residing >>>> on the FC storage and select to start on any node on the cluster, they >>>> always start on the SPM. Can multiple nodes run different VM's on the >>>> same >>>> FC storage at the same time (logical thing would be that they can, but I >>>> wanted to be sure first). I am not familiar with the logic oVirt utilizes >>>> that locks the vm's logical volume to prevent corruption. >>>> >>>> - Fdisk shows that logical volumes on the LUN of the FC volume are >>>> missaligned (partition doesn't end on cylindar boundary), so I wonder if >>>> this is becuase I imported the VM's with disks that were created on local >>>> storage before and that any _new_ VM's with disks on the fc storage would >>>> be propperly aligned. >>>> >>>> This is a new setup with oVirt 3.4 (did an export of all the VM's on 3.3 >>>> and after a fresh installation of the 3.4 imported them back again). I >>>> have room to experiment a little with 2 of the 4 nodes because currently >>>> they are free from running any VM's, but I have limited room for >>>> anything else that would cause an unplanned downtime for four virtual >>>> machines running on the other two nodes on the cluster (currently highly >>>> available and their drives are on the FC storage domain). All in all I >>>> have 12 VM's running and I'm asking on the list for advice and guidance >>>> before I make any changes. >>>> >>>> Just trying to find as much info regarding all of this as possible before >>>> acting upon. >>>> >>>> Thank you in advance, >>>> >>>> Ivan >>> _______________________________________________ >>> Users mailing list >>> Users(a)ovirt.org >>> http://lists.ovirt.org/mailman/listinfo/users