Cisco MDS Zoning

Single initiator with a single target is the most efficient approach to zoning

Just jotting down some links

http://www.cisco.com/en/US/docs/switches/datacenter/mds9000/sw/4_1/configuration/guides/fm_4_1/zone.html

http://routerjockey.com/2011/12/23/mds-fiber-channel-switching-basics-for-network-engineers/

EMC VNX Storage Pool Design & Configuration

The EMC Whitepaper on VNX Best Practices h8268_VNX_Block_best_practices.pdf is the way to go, I used version 31.5 as it is the most current one available.

Storage Pools vs Raid Groups vs MetaLuns

From an design perspective, MetaLuns were basically replaced by Storage Pools, Storage pools allow for the large stripping across many drives that MetaLuns offers, but with a lot less complexity. MetaLuns are now generally used to combined/expand a traditional LUN.  Raid Groups have a maximum size of 16 disks, so for larger strips this isn’t a viable option.  For situations where guaranteed performance isn’t critical, go with Storage Pools, use Raid Groups if you need deterministic (guaranteed) performance.  The reason behind this is that you are probably going to create multiple LUNs out of your storage pool, so this could lead to one busy LUN affecting the others.

Raid Level Selection

Assuming your going with a Storage Pool, your options are Raid 5, 6, or 1/0.  If you are using large drives (over 1TB) then Raid 5 is not a good choices because of long rebuild times, Raid 6 is almost certainly the way to go.  Always use suggested drive numbers in the pools, Raid 5 is 5 disks, or a number that evenly divides by 5, Raid 6 & Raid 1/0 is 8 disks or a number that evenly divides by 8.  If you use less than the recommended you will be wasting space.

How Big of a Storage Pool do I start with?

Create a homogeneous storage pool with the largest number of practical drives.  Pools are designed for ease-of-use.  The pool dialog algorithmically implements many Best Practices.  It is better to start with a large pool, as you add disks to the pool, it does not (currently) restripe the disks, and therefore if you only added 5 disks to an existing 50 disk pool, the new LUNS would have much lower performance.   The smallest practical pool is 20 drives (four R5 raid groups).  It is recommended practice to segregate the storage system’s pool-based LUNs into two or more pools when availability or performance may benefit from separation. 

I am only covering a small portion of what you need to know.

When dealing with storage, there are thousands of options, homogeneous drives vs. heterogeneous, Thick vs. Thin Provisioning, Fast VP Pools, Drive Speeds, Fast Cache and Flash Drives, Storage Tiering, the whitepaper above does a great of of detailing all of that, I won’t try to improve on what EMC has said.

Changing passwords on a TFS (Microsoft Team foundation server 2008) Service Account

DISCLAIMER: I am not an TFS expert, at all. 

Besides the normal of modifying the password in service manger, I found a few other things.

Hopefully it’s a VM so you can take a snapshot before you do anything.

Much of this data I got from “How to change the Service Account or Password for Team Foundation Server”

1) SQL reporting services will need to get updated, I believe you can do it through the TFSAdminUtil with the /ra option, or you can run through the Reporting Services Configuration again.

2) You may need to modify service account passwords on IIS Application Pools, such as the “Microsoft Team Foundation Server Application Pool” under Identity update the password, I had to update 3 of my pools.

Good Luck!

VCDX #91

I learned yesterday am that my defense was successful. What a long journey, and I passed everything the first time, I can only imagine what others have gone through. I am thrilled to join such an elite community of VMware professionals.

VCDX thoughts

I am right in the middle of my wait for VCDX results, so I thought I'd share some thoughts before I know if I pass or not
1) The questions were fair, that doesn't mean I knew the answers, just that I probably should/could have.
2) It's alot more fair than any electronic test.
3) Stay calm, don't let them run you down to crazy town, actually that's not true, they got me off balance, I ran down to crazy town all by myself.
4) Be confident, show your thought process, but admit what you don't know, you can't BS these guys.
5) If I don't pass I look forward to doing a better job next time.
6) The wait is just awful, 10 business days will give you ulcers if you let it.

EMC world 2012 day 1 thoughts

Attended some great sessions on vSphere performance, power path optimizations, vcops vnx plugin -integration , view IOPS performance, vf-cache (taking Storage cache into the server)
Good stuff, excited to be at day 2!

Lab Manager ESX 4.1 Host can’t join back into Lab Manager, reporting error “Host is entering maintenance mode”

Recently upon pushing patches to our ESX 4.1 and ESXi 4.1 hosts, I was unable to re-enable 2 of our 23 blades.  We had one of each flavor, ESX and ESXi.  After much frustration I found our KB 1026364, which says:

===================================================

To resolve this issue, restart the Lab Manager VSLA backend service.

To restart the VSLA backend service on Lab Manager:

1. Log in to the Lab Manager server.
2. Go to Start > Run and type service.msc.
3. Right click the VMware vCenter Lab Manager Monitor service.
4. Click Restart.

When you restart the Lab Manager VSLA service , the DVS becomes unavailable. When the service starts again, Lab Manager gets the latest status from the vCenter Server.

After the Lab Manager VSLA service starts again, you can start repairing the ESX hosts or try re-enable host-spanning within Lab Manager.

===================================================

After restarting this service, I was able to repair our Hosts without issue.