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I have a few virtual servers running on a VMWare-ESXi server. One of those is a mailserver running Windows server 2003, Has been running quite well for a while now. About 4 days ago, the mailserver runs beautifully for about 5-8 hours at which point it slows down to an unusable crawl.

When I try to VM into the server it most likely tells me that it' can't connect and I can't see what's going on.

When I try to ping the server, it usually drops 2-4 packets, ping 2 seconds later a different 2-4 packets with the pingback time ranging from <1 to 200+ wtih a few request timeouts and somethimes a destination unreachable. In fact on some pings I get destination unreachable, request time out, and success at <1ms pingback. And not in that order.

To remedy the situation I do an F12 reboot of the physical machine and start up the virtuals inside one by one, Then I get a few hours before it starts crawling again.

But before I start up ANY virtual machines I get the same unstable ping behaviour when pining the server's management adress. If I ping the virtual servers when everything runs nicely I get no packet loss. When I VMWare to manage the server because I need to boot up the virtuals I will frequently see it lose the console and get it back.

This server is 1 of 4 twins in a rack the other twins have no such problem, very solid, very fast, ping anything <1ms no loss.

Has anyone encoutered a similar problem or does the behaviour ring a bell.

Am I looking at hardware failure or bad config/software?

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Need to have some more info. How are the vSwitches configured (separate for management and guest traffic? How many physical NIC's on each vSwitch?) Have you checked the switches you're plugged into for port/cable issues/etc? – Rex Oct 17 '12 at 17:20
1. What VMware product are you using, specifically? 2. How do you "VM" into a server? 3. Are you referring to "VM'ing" into the host or the guest? – joeqwerty Oct 17 '12 at 20:54
I've been having a similar problem. we removed another server that had "died" (but was still plugged in) and so far the problem hasn't returned after 8 hours, but it's been so intermittent, sometimes going for days between incidents of horrible packet loss, I don't want to get my hopes up yet. – user16081-JoeT Feb 11 '13 at 0:16

I'm ashamed to admit that the problem was resolved by reseating the hard drives, reseating the memory and giving the server a good shake in the process.

Thanks to all who took interest.

Moderators should probably close this one.

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