VMs losing network connectivity after reboot

[Fred_Weston]

My company set up a new ESXi cluster about 3-4 months ago and several times have noticed that after rebooting to install Windows Updates the Windows guests can no longer communicate with the network.  The network adapters still show connected and the static IP configuration is still present if I view the IPv4 properties in Windows, however Windows shows that it's connected to an unidentified network.  The VM cannot ping anything and nothing can ping the VM.  If I disable the adapter in Windows on the affected guests and then immediately reenable it, the problem goes away.

We are running vSphere Server Appliance Version 5.5.0 Build 2026576 and VMware ESXi, 5.5.0, 2068190.  The VMs in question are Windows 2008 R2 Data Center and are up to date on both Windows Updates and VMware Tools.  They are using the e1000 network driver and are version 10 VMs.

Any suggestions on what I need to do to prevent this issue from occurring in the future?

[ewallers]

I am experiencing the same issue.

I have not had the issue appear more than once per server, but with over 70 VM's, each time causes much frustration grom my customers. this morning it was our DHCP server.....

[Granty]

Have you tried replacing your E1000 network adapters with the VMXNET alternative?  I went through the process of replacing all NICs to VMXNET3's on all of my VMs and as well as improving performance, it has resolved a very similar problem with VMs losing connectivity.

[ewallers]

I have been using VMXNET3's on all my servers since v4.5, so that is not something I can change.

I tried looking into the registry edit (HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces - edit the keys for the 169.x.x.x address) but there were no 169.x.x.x addresses, so that didn't work.

I had two servers "lose" their IP just this last week.

From the research I have found, it is suggested that this occurs to systems that have upgraded from 4.x to 5.x, which we did, but I still haven't found any solution.

Thanks for the suggestion though.

[TacoSauce]

Same issues over here. Since a couple of weeks a dozen vm's (Windows and Linux) losing their connectivity after a restart or a reboot action.

All our servers use the VMXNET3 adapter. The issue occurs in our esxi 5.5.update 2 environment and in our esxi 6.0 environment.

Cheers,

Wouter

[ewallers]

We have been having this issue for quite some time and have gotten no where. I thought is was just VMware, since that is the only servers that had the issue, but recently in a isolated lab/test environment, we had the same issue occur... to a physical server. All our research points to a bad IOS version on a Cisco switch/router. Our Cisco equipment is two devices beyond the VMware environment (1.Dell switch, 2.Brocade switch, 3.Cisco 6509 router/switch). I have not been able to completely verify this, since my Cisco engineer is swamped and can't get to updating our core router, but I wanted to share so those of you pulling your hair out might be able to have some hope and look in a different direction.

[TacoSauce]

Thnx, very useful information. We also use Cisco 6500 switches. Maybe it's not only vmware related.