We help IT Professionals succeed at work.
Get Started

Why is my SAN/Restore so slow?

hongedit
hongedit asked
on
631 Views
Last Modified: 2012-08-14
Hi all

Last night I made a massive mistake and managed to delete the 2 vmdk's containing my Exchange Mailboxes and Logs.

Never fear, for I had done a full backup of the VMDK's earlier that day with VMWare Data Recovery.

At 2:30am it had completed 20%. Its now 13:45 the next day and its still on only. 75%

Monitoring the SAN using Resource Monitor, I can see Disk I/O is sitting at around 5-10MB/sec. Network Utilisation is around 100-120Mbps.

This was done on a bit of a budget as detailed below but it still should not be this slow in my opinion. Where is my bottleneck?

THe iSCSI SAN Disks are NL SATA disks. Yes I know, but still should not be this slow?

There are 5 1Gb links going into the SAN Switch (seperate network to Data), but only 1 of these are operational as I messed up the Link Teaming (chose wrong type).

Could it be this? Surely if this was maxing out, it'd be at 90%+ utilisation?

The disks are 4 NL SAS (SATA) disks in Raid 5 or 6 (cant rememebr which, and I cant access the concole right now).

Using DiskSpeed, the Max Read speed is clocked at 229.82MB/sec. Which is miles from 5-10MB/sec its operating at for this restore.

The Data network (which is the VM Management and Client Access network) is only 100Mbps (this will change to a GB Switch later this week), but I dont think the restore needs to even touch the data network?

Where is my bottleneck?

I'll see if I can knock up a quick diagram.
Comment
Watch Question
VMware and Virtualization Consultant
CERTIFIED EXPERT
Fellow
Expert of the Year 2017
Commented:
This problem has been solved!
Unlock 1 Answer and 22 Comments.
See Answer
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE