VMWare showing 20GB instead of 40Gb

[KG Support]

We just added a new UCS chassis and 8 B200's.  We have ESXi 6 configured on them and up and running VM's on them.  However, we have noticed that our old blades in our existing chassis show 40GB for the vnic's in ESX.  Same profiles being used on the UCS side for the configuration.  Why are the vnics not showing up as 40Gb on the ESX side?

[Walter Dey]

I assume this are B200-M4 with which I/O Adaptor and which model of IOM ? 2204 or 2208 ?

Most likely your other servers were B200-M3 with VIC 1240 and extender plus IOM 2208.

see eg. Tab 9 in

http://www.cisco.com/c/dam/en/us/products/collateral/servers-unified-computing/ucs-b-series-blade-servers/b200m4-specsheet.pdf

Walter.

[KG Support]

B200-M4 are the new ones we are working with. Both old and new have 2208 IOMs.  We have FI but no VIC's that I can see.

[Walter Dey]

The difference most likely is: old blade has VIC-1240 + Extender, the new one only VIC without Extender.

[KG Support]

How can we confirm that?  Where is the VIC + Extender listed in the UCS System Manager?

[Walter Dey]

Equipment -> select blade
Inventory -> Adaptors

see attachmemt

[KG Support]

It appears we have VIC 1340's in the new servers and 1240's in the old.

[Walter Dey]

No, this is not the explanantion; VIC 1340 and 1240 are equivalent regarding the internal wiring over chassis backplane to the IOM.

see e.g.http://www.cisco.com/c/dam/en/us/products/collateral/servers-unified-computing/ucs-b-series-blade-servers/B200M3_SpecSheet.pdf

Fig 10, and Fig 11. which explains your findings

5Fi

[Joe Galvan]

Actually, in ESX the vnics using the 1240s always show as 40 GbE and the 1340s show as 20 GbE, regardless of the expander.  

[pieman2015]

Why is this the case?

[Walter Dey]

I'm fairly convinced it is related to below issue:

https://supportforums.cisco.com/discussion/12565226/vic-1340-pci-placement-issues

It looks like Cisco made some changes with the VIC 1340 card installed in B200 M4 blades.  These cards now have two PCI paths which result in effectively appearing to have two adapters, without actually appearing to have two adapters (you won't see a second adapter listed in server inventory, but you do now have two distinct PCI ID trees).  Cisco bug ID CSCut78943 has more information on this.  It appears that now if you have a VIC 1340 card you now have the ability to specify a host-port (controlled in PCI placement screen) to tell UCS what port of the 1340 the virtual adapter should be using.

Walter.