Volume snapshots disappearing? "Barkley Bees" <barkleybees[ at ]hotmail.com> 12/17/2008 3:45:59 PM I have deployed two identical servers (Storage Server 2003 R2 SP2 x64 - Dell NF500 + MD3000) with DFS Namespaces and Replication and one shared folder on the D: volume. This folder (Users) replicates between the two servers. I have also configured Volume shadow copies on the D: volume of each server and assigned 3.8TB for the shadow data (total volume is 10.9TB). I have decided to keep the default schedule of 7am and 12pm for now. Anyhow, for the first week or so it was taking snaps with no problem. Then the other day I had about 10 pilot users copy their user folder data to the new server (total ~12GB). All seemed well with replication working correctly between the servers but then today I noticed that the volume snapshots are disappearing which is quite dismaying to say the least. For the last two days I am seeing the below in the event log: -------------------------------------------------------------------------------------------------------------------- Event Type: Error Event Source: VolSnap Event Category: None Event ID: 25 Description: The shadow copies of volume D: were deleted because the shadow copy storage could not grow in time. Consider reducing the IO load on the system or choose a shadow copy storage volume that is not being shadow copied. -------------------------------------------------------------------------------------------------------------------- I understand that under high IO load (as the error message states) that this has been known to happen but this is with only 10 test users. We have another file server (2TB of data) with VSS enabled and accessed by ~500-750 users that has never experienced this issue. It, like the new server, is saving the volume snapshots to the same volume as the data. I'm unsure as to what may be the actual cause here. Is it incorrect for me to have VSS enabled on both servers that are replicating to each other (I wouldn't think is related). Appreciate any advice or feedback from folks who may have experience this or similar. Note: I verified that disk write cache is not disabled. http://support.microsoft.com/kb/826936 (several other similar kb's on the matter but no clear resolution yet)

Re: Volume snapshots disappearing? HAL07 <yahoohal[ at ]online.yahoo.com> 12/19/2008 8:33:44 AM I have also this problem, and it seem to be a common problem on all our fileservers. (Windows 2003 and 2003 R2's. 32bit) This is not related to replication, but in general the filesystem that fails to grow. I've tried resolving it several times, but I've never found time contacting Microsoft on it. So if you find a solution, please post it! :) Barkley Bees wrote: [Quoted Text] > I have deployed two identical servers (Storage Server 2003 R2 SP2 x64 - Dell > NF500 + MD3000) with DFS Namespaces and Replication and one shared folder on > the D: volume. This folder (Users) replicates between the two servers. > > I have also configured Volume shadow copies on the D: volume of each server > and assigned 3.8TB for the shadow data (total volume is 10.9TB). I have > decided to keep the default schedule of 7am and 12pm for now. > > Anyhow, for the first week or so it was taking snaps with no problem. Then > the other day I had about 10 pilot users copy their user folder data to the > new server (total ~12GB). All seemed well with replication working correctly > between the servers but then today I noticed that the volume snapshots are > disappearing which is quite dismaying to say the least. For the last two > days I am seeing the below in the event log: > > -------------------------------------------------------------------------------------------------------------------- > Event Type: Error > Event Source: VolSnap > Event Category: None > Event ID: 25 > Description: > > The shadow copies of volume D: were deleted because the shadow copy storage > could not grow in time. Consider reducing the IO load on the system or > choose a shadow copy storage volume that is not being shadow copied. > -------------------------------------------------------------------------------------------------------------------- > > I understand that under high IO load (as the error message states) that this > has been known to happen but this is with only 10 test users. We have > another file server (2TB of data) with VSS enabled and accessed by ~500-750 > users that has never experienced this issue. It, like the new server, is > saving the volume snapshots to the same volume as the data. > > I'm unsure as to what may be the actual cause here. Is it incorrect for me > to have VSS enabled on both servers that are replicating to each other (I > wouldn't think is related). Appreciate any advice or feedback from folks who > may have experience this or similar. > > Note: I verified that disk write cache is not disabled. > http://support.microsoft.com/kb/826936 (several other similar kb's on the > matter but no clear resolution yet) > >

Re: Volume snapshots disappearing? "Barkley Bees" <barkbees[ at ]nomail.com> 12/22/2008 2:47:42 AM Sadly, it has still been occurring on a daily basis. Here's my plan off attack: 1. As a first step today, I have installed the following patch to the secondary replication server: Installed - KB943669 http://support.microsoft.com/default.aspx/kb/943669/en-us (will watch for results and update) 2. If the above does not resolve the matter I will look at testing the following: http://support.microsoft.com/default.aspx/kb/826936/en-us. I will create a new registry entry "MinDiffAreaFileSize" in "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VolSnap" and give it a value of 3000 (3GB). 3. Then finally, if I must, I will reformat the drive to use 16k cluster size (instead of the 4k default) as this is stated to be the best practice when it comes to using VSS - http://support.microsoft.com/kb/312067/. A very good reference here which I think pinpoints the problem: http://duitwithsbs.wordpress.com/2008/07/21/drive-formatting-16k-cluster-to-avoid-loss-of-volume-shadow-copy-snapshots/ The strange thing is that another separate server (mentioned in my original post) has been in use for over a year and is formatted using 4K cluster size and never had this VOLSNAP EventID 25 occur once (never lost any snapshots). Then again this new server is a fair bit larger in terms of capacity, using Dynamic disks to span several large volumes, and also DFS-R. Has anyone else been up this alley and found a valid solution? MVP folks also? "HAL07" <yahoohal[ at ]online.yahoo.com> wrote in message news:eXKppSbYJHA.6000[ at ]TK2MSFTNGP05.phx.gbl... [Quoted Text] >I have also this problem, and it seem to be a common problem on all our >fileservers. (Windows 2003 and 2003 R2's. 32bit) > This is not related to replication, but in general the filesystem that > fails to grow. > > I've tried resolving it several times, but I've never found time > contacting Microsoft on it. So if you find a solution, please post it! :) > > Barkley Bees wrote: >> I have deployed two identical servers (Storage Server 2003 R2 SP2 x64 - >> Dell NF500 + MD3000) with DFS Namespaces and Replication and one shared >> folder on the D: volume. This folder (Users) replicates between the two >> servers. >> >> I have also configured Volume shadow copies on the D: volume of each >> server and assigned 3.8TB for the shadow data (total volume is 10.9TB). I >> have decided to keep the default schedule of 7am and 12pm for now. >> >> Anyhow, for the first week or so it was taking snaps with no problem. >> Then the other day I had about 10 pilot users copy their user folder data >> to the new server (total ~12GB). All seemed well with replication working >> correctly between the servers but then today I noticed that the volume >> snapshots are disappearing which is quite dismaying to say the least. For >> the last two days I am seeing the below in the event log: >> >> -------------------------------------------------------------------------------------------------------------------- >> Event Type: Error >> Event Source: VolSnap >> Event Category: None >> Event ID: 25 >> Description: >> >> The shadow copies of volume D: were deleted because the shadow copy >> storage could not grow in time. Consider reducing the IO load on the >> system or choose a shadow copy storage volume that is not being shadow >> copied. >> -------------------------------------------------------------------------------------------------------------------- >> >> I understand that under high IO load (as the error message states) that >> this has been known to happen but this is with only 10 test users. We >> have another file server (2TB of data) with VSS enabled and accessed by >> ~500-750 users that has never experienced this issue. It, like the new >> server, is saving the volume snapshots to the same volume as the data. >> >> I'm unsure as to what may be the actual cause here. Is it incorrect for >> me to have VSS enabled on both servers that are replicating to each other >> (I wouldn't think is related). Appreciate any advice or feedback from >> folks who may have experience this or similar. >> >> Note: I verified that disk write cache is not disabled. >> http://support.microsoft.com/kb/826936 (several other similar kb's on the >> matter but no clear resolution yet) >