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Tuesday, 6 August 2013

Cisco VIC 1225 with VMware | Redundant Networking Problem

Hi all,

I have been installing some Cisco C220 servers with the VIC 1225 CNA (converged network adapter) for a local company. As part of the installation these servers were connected to a pair of Nexus 5K's with the CNA used for both fiber channel and 10gbps ethernet for VMware ESXi 5.1.

The connectivity was pretty standard to any installation of this type with one 10 gig link going to one switch and the other going to the second switch, exactly like if this was a 1 gig implementation with catalyst switches. So i installed VMware and as part of the default installation vmware takes the first network card and uses that as its management interface and also uses the MAC address of that NIC for the MAC address of the management console. FINE! But that will come back and trouble me later on.

So i give the management interface a static IP address and connect using the vSphere client and all's going well until the point where i add the second NIC, and all connectivity to the host was lost!  So i connect the CIMC and run the test network connectivity and everything fails. So i remove one of the NIC's and everything comes back up again. So after lots and lots of testing and nothing working when everything looked correct, we resulted in logging a support call with Cisco.

It turns out that there is currently a fault on the VIC 1225 where by, even though all the vNIC's are in promiscuous mode, if one port see's the MAC address of another vNIC it doesn't forward the packet. I have been told that there is a fix on the way and should be available in September.

So the solution, if you get this as a problem is to delete the default VMware management interface and create a brand new one, this is given a VMWare MAC address stating in 00 and is therefore not a MAC address that appears on the VIC. Add your two network to this new management interface and everything works as you would expect.

Thanks for reading and i hope this was of use to someone.

Monday, 13 May 2013

Installing ESXi onto new Dell Servers

Hi all,

just a quick post, i've recently had to install ESXi onto some new Dell server (R720 and the 1u equivalent) for some clients. I normally download the latest release from VMware and burn it to CD before i go to site to save some time, but this has caught me out with the new Dell Servers.

What you will find is that when the ESXi disk starts to boot you get an error message stating that there are no network cards in the server (even though i had on this occasion 2x quad port broadcom NIC's). What you need to do is go to Dell's website, enter in the server tag for the server you have purchased and got to the enterprise solutions part of the support and drivers section. There you can download a Dell customized version of ESXi which includes all the dell drivers you need to successfully install ESXi

Hope this helps and thanks for reading.


Thursday, 7 February 2013

Increase VMware converter performance

Hi All,

I was involved with a P2V migration last week and while the number of servers to migrate were small the amount of data held on these servers were around 250gb - 500gb in size. This conversion was to a vSphere 5.1 infrastructure using the VMware standalone converter running in a VM. When i started the migration off, we were experiencing terrible transfer rates in the region of 2MB/s and it was saying well over 8 hours of the P2V to complete per server.

After a little bit of googling i found the following article on VMwares communities forum which says that from converter 5.0 and onward, the transfer of data has been encrypted by default and that this could slow down the transfer of data.(

I stopped the job and turned off the encryption by editing the converter-worker.xml file and started the job again. The transfer rate, once stabilized went up to around 25MB/s and drastically reduced the amount of time the P2V took!

If you are experiencing slow P2V rate this might be something worth trying.

kind regards and thanks for reading