Snapshots created with EqualLogic VSS Provider do not display in SAN HQ

Question

Hello, First-time poster. We just implemented an EqualLogic PS6100X SAN and we're having performance problems between our DPM backup server, one of our Hyper-V hosts, and VM images that are stored on the SAN. I'll try to provide as much information as I can Environment: Dedicated iSCSI network using Dell Force10 switches 3 Hyper-V Hosts (Windows Server 2008 R2)- 2 of the hosts have a dedicated 4-port GB NIC connected to the iSCSI network; 1 host has a dedicated 2-port GB NIC connected to the iSCSI network- Each Hyper-V host has a dedicated RAID-50 volume on the EQ SAN, which stores the Hyper-V VMs- EQ VSS provider installed on all 3 Hyper-V hosts and working correctly Using DPM 2010 for backup Problem: On Hyper-V hosts 1 and 2, any/all backup-related activities are painfully slow. On the 3rd Hyper-V host, however, any/all backup-related activities are blazingly fast! We've compared NIC configurations, HIT/ME and ASM settings, but we can't figure out why it is so slow on hosts 1 & 2. On top of that, whenever DPM 2010 tells the EQ VSS provider to create a snapshot, we see the snapshot being created in the EQ Group Manager, but it doesn't show up in the iSCSI Connections list. According to the SAN HQ documentation, snapshots as well as volumes should show up here. We've also turned off TcpAckFrequency for all 3 hyper-v hosts. This has helped somewhat, but there is still a HUGE difference with regard to DPM backups.We're pretty sure that there's something configured incorrectly on Hyper-V hosts 1 & 2, since Hyper-V host 3 does not have performance problems.How do I get snapshots to appear in the iSCSI Connections list in SAN HQ? Version info:SAN HQ = 2.2.0.5924Storage Array Firmware = 5.2.4

EqlHIT1 · Accepted Answer

There are two different issues in this post, for the SANHQ not showing iSCSI Connections,

At present SANHQ shows the correct total connection count but does not provide details of individual iSCSI connections for snapshots, which it should. So in the meantime use the Group Manager which shows the details for each snapshot (I know that's not the best answer, its a short term workaround).

The fact the SANHQ does not show details of snapshot connection does not mean they are not there and I can't imagine anything to do with the DPM issue.

For real fix, look for upcoming beta of SANHQ and signup for that on the EQL support site. You can do that now.

mstrode_AxiomEP · Answer

Follow-up

I noticed the following when looking at iSCSI session info in the iSCSI Connections section of SAN HQ:

"The iSCSI session information does not include data for Replication Management and Host Control Management sessions."

Would this include snapshots created by the EqualLogic hardware VSS provider, which is triggered by MS DPM 2010?

VR6Alan · Answer

Does the DPM server sit on Hyper-V host 3?

mstrode_AxiomEP · Answer

I'm not having any problems with DPM 2010 and iSCSI HW snapshots, especially when creating recovery points for Hyper-V snapshots that reside on a SAN volume. This applies for all three of my Hyper-V hosts. The DPM agent is triggering the iSCSI HW provider, the snapshot is getting created, and DPM is backing up the snapshot (all according to expectations).

I was merely curious as to why, when a DPM-triggered snapshot is created, I don't see the snapshot volume appear in the iSCSI Connections section in the SAN HQ software. I see the snapshot get created in the EQL PS Group Manager, I see regular volumes, and I see, when a DPM-triggered snapshot is created, an increase in the number of iSCSI connections. I just don't see the snapshot volumes appear.

Even if it's just because of the way DPM triggers the creation of the snapshot volume, I'm ok with that. I just want to make sure I'm not missing something because I can't see any connection-related data (read, write, IOPS, I/O Rate) for those volumes.

mstrode_AxiomEP · Answer

Thanks! That's what I wanted to hear.

I've been troubleshooting performance problems between DPM and the SAN. I do monitor the snapshots in Group Manager, so that is somewhat helpful. But the Group Manager, unfortunately, isn't as robust as SAN HQ when it comes to providing I/O, network, and other performance metrics. I'll check into the upcoming SAN HQ beta. Thanks again!

FluidFS

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