Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

This is an odd issue I've had with a network I formerly admined. We found a workaround, but the core issue remains unknown to me.

Situation is a pair of ESX hosts in a cluster. Each had their VMs on their local hard drive. We added a SAN and connected it to the ESXs. After migrating the VMs to their new storage, a curious event occured.

Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=1546ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128
Reply from myvm: bytes=32 time=3ms TTL=128

Notice the exception? Inside the VM, everything was just fine and dandy, except that on a totally random timing, stuff seemed to quasi-freeze (for a very short timespan) then back to normal. This was not a storage issue, as any VM created straight on the SAN did not exhibit this issue. Our workaround was simply creating most of our servers from scratch (for a variety of reasons, this was quite simple).

Any ideas what could have caused this?

share|improve this question
5  
Do you have DRS enabled? That looks light a high priority vMotion to me –  Zypher May 27 '11 at 17:05
    
Where were the VM swap files located? –  joeqwerty May 27 '11 at 19:05
    
@Zypher, DRS was enabled but there was no vMotion involved. –  Daniel Goldberg May 27 '11 at 20:31
    
@Joeqwerty, with the VMs. You're suggesting it might be that the swap files were not migrated? –  Daniel Goldberg May 27 '11 at 20:31
1  
Yes, although I'm by no means a VMware expert. –  joeqwerty May 27 '11 at 21:05
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.