Return to Blogging and Recent updates

So for a while now i was “stuck” pretty much living in Southern California doing some interesting work, however it was slowing sending me to a dark place.

Anyway i am now back in PA and doing some pretty cool work lately. I will be writing a bunch of stuff again, and trying to update a lot of my older stuff.

I have been doing a lot of work on my own with ZFS which has been a BLAST!! I can get some pretty impressive IOPS out of just my little array at home.

I just did a UCS deployment for a 20,000 seat XenDesktop setup. They will be using the new Cisco Invicta array, which was Whiptail. Seems really cool, i’m trying to assist the customer with whatever they need, maybe get in on a whitepaper 🙂

I have a bake-off upcoming with a new NetApp 6280 vs a ZFS based Oracle array. This is Nerdtastic!! I’ll be doing a pretty deep writeup on this as prior around the test-cases and afterword as well with the results.

I am attending my first Cisco Live ever, and i have to say i haven’t been this excited for a conference in some time. I’d have to clone myself 3 times over to hit all the sessions i want to hit. Hopefully the outcome meets my expectations.

Custom UCS/FlexPod Build Script

 UPDATE: Working with some of our internal guys, its come to my attention that some of the script has broken with the newer UCSM versions.  I will be updating this to be more “adaptable”, however use the script for ideas and feel free to kang any code from it for now.


 

So i started working on developing a Powershell script that will grab variables from an Excel sheet and create a UCS Build off of that.

I am at a point that the build actually works quite well now. I’m pretty proud of myself since i’m NOT a deep Powershell guy. This came about from looking at other UCS Powershell scripts and a lot of tweaking and testing.

Anyway this script will continue to grow and its functionality expand. My end goal is to be able to do a base FlexPod build by scripting, including UCS, Nexus Switches, Netapp and VMware.

It will take a lot of time, and i may never really use the script but its more of a pet project to not only see if i can do it, but also grow my Powershell skillset.

Here is the github if you’d like to follow/assist or download and play with it a bit.

https://github.com/cknic/UCS_Build

iSCSI Boot with ESXi 5.0 & UCS Blades

UPDATE:: The issue was the NIC/HBA Placement Policy.  The customer had set a policy to have the HBA’s first, then the iSCSI Overlay NIC, then the remaining NICs.  When we moved the iSCSI NIC to the bottom of the list, the ESXi 5.0 installer worked just fine.  I’m not 100% sure why this fix is actually working, but either way it works.

So at a recent customers site i was trying to configure iSCSI Booting of ESXi 5.0 on a UCS Blade, B230 M2.  To make a long story short it doesn’t fully work and isn’t offically supported by Cisco.  In fact, NO blade models are supported for ESXi 5.0 & iSCSI boot by Cisco.  They claim a fix is on the way, and i will post an update when there is a fix.

Here is the exact issue, and my orgianal thoughts, in case it helps anybody;

We got an error installing ESXi 5 to a Netapp LUN.  Got an error “Expecting 2 bootbanks, found 0” at 90% of the install of ESXi. The blade is a B230 M2.

The LUN is seen in BIOS as well as by the ESXi 5 installer.  I even verified the “Details” option, and all the information is correct.

Doing an Alt-F12 during the install and watching the logs more closely today, at ~90% it appears to be unloading a module, that appears by its’ name, to be some sort of vmware tools type package.  As SOON as it does that the installer claims that there is no IP address on the iSCSI NIC and begins to look for DHCP.  The issue is during the configuration of the Service Profile and the iSCSI NIC, at no time did we choose DHCP, we choose static. (We even have tried Pooled)  Since there is no DHCP Server in that subnet it doesn’t pickup an address and thus loses connectivity to the LUN.

So we rebooted the blade after the error, and ESXi5 actually loads with no errors.  The odd thing is that the root password that’s specified isn’t set, it’s blank like ESXi 4.x was.

So an interesting question is what’s happening during that last 10% of the installation of ESXi 5??  Since it boots cleanly, it almost seems like it does a sort of “sysprep” of the OS, ie all the configuration details.  If that’s the only issue then it might technically be ok.  However I don’t get the “warm and fuzzies”.  My concern would be that, maybe not today but down the road some module that wasn’t loaded correctly will come back to bite the client.

Also, what is happening in that last 10% that’s different then ESXi 4.x??  We were able to load 4.1 just fine with no errors.

Again we called Cisco TAC and we were told that ESXi 5 iSCSI booting wasn’t supported on any blade.  They do support 4.1 as well as Windows, and a variety of Linux Distos.

Configuring iSCSI boot on a FlexPod

Here is a nice document to follow to configure iSCSI booting for a FlexPod, ie. UCS Blades, NetApp array & ESXi.

UPDATE: This document has the fix i found for ESXi 5.0.  This was tested on B230 M2’s and seems to work every time.

This document will be updated as i get new information.

FlexPod iSCSI Boot-Fixed

Direct Connected Fiber Storage to UCS

So i’ve come across this recently.  I have a client that is direct connecting the Fiber from their NetApp array to the 6120’s of the UCS.

The issue that has been raised is that this is not technically supported.  As is seems Cisco releases with the 1.4.1 firmware release that you can absolutely do this.  However there is a caveat, it’s supported by Cisco as long as the storage vendor will support it.

The biggest problem is that NetApp did support it, but they don’t any longer.  So it seems Cisco was left holding the ball when NetApp walked away.

So if your running a NetApp array that is direct connected to their UCS w/o an MDS or even a 5548 with the FC module, its no longer technically supported and you very well may run into issues if you need Vendor support.

For those not familiar with direct connecting the storage i’ll give a little but of information on it, as well as some of my experiences with it and some tips on making it “work” with UCS.

So inside the 6120 there is effectivly a very very dumb MDS switch.  There is no Zoning, it is all 1 big zone, you do vSANs, but obviously no inter-vSAN routing, no security, no real way of even getting any initiator/target information for troubleshooting purposes.

In order to even use the functionality, you must change the Fiber portion of the switch from “End-Host Mode” to “Switch Mode”.  This is EXTREMELY similar in method and functionality to switching the Network side to “Switch Mode”.

You MUST also make sure to select the default vSAN that is created upon inital set-up, and enable “Default Zoning”

Intersting note you MUST absolutely make sure the HBA name in the Boot Policy is the EXACT same as the HBA name in the HBA Template, or it won’t boot.
So again, in my opinion if you can avoid direct connecting your SAN storage to the 6120, please avoid it, at least until UCS 2.0 comes out  🙂