UCS

Last month we began the process of upgrading all our UCS domains to the newer 4.1 code release trains to enable new functionality/hardware and resolve some minor bugs. After we completed our first domain we were treated to a new fault code on each Fabric Interconnect, approximately 45 minutes after it’s individual upgrade completed. The fault code thrown was “Partition bootflash on fabric interconnect X is clean but with errors.” As this domain happened to be the very first UCS domain we ever had we assumed it may be an issue with the actual NVRAM in the FI. We triaged the case with TAC and determined that this was just enhanced file system checking in the 4.1 code train and that the fix is to run a e2fsck against the bootflash. In previous versions of UCS this would require the debug utility and manually running some commands. However, in 4.1(2a) and 4.0(4k) Cisco added the ability to run a e2fsck from the UCS CLI on the Fabric Interconnect. We figured this would be a one-off case, isolated to this domain, and didn’t think much of this. ...

Anyone that has spent any time with Cisco equipment should just come to expect that there’s a number of VLANs that Cisco reserves for internal use. Cisco UCS is no exception. However, in UCS land, there’s a few curve balls you need to be aware of from version numbers and hardware types. As I just completed an internal documentation of these VLAN IDs for our department, and since there’s a few places these are documented on Cisco’s web site, I felt it may make sense to just put them here for easy consumption later. In addition to the Cisco official documentation I’ve included my recommendations for reserving additional VLANs to make your life easier. ...

Note: This process should work for Windows and Linux as well. Verify the EFI boot path for the OS. Through ESXi 6.0 I have run my hosts in Legacy BIOS mode on UCS. There just was nothing significant enough worth the hassle of switching to UEFI on UCS (rather: I had more important fires to put out…). The one feature I did want, Secure Boot, wasn’t supported by ESXi 6.0 and earlier. ...