Luke

VMware’s Advanced Options for HA Cluster – das.slotCpuInMhz das.slotMemInMB das.SlotNumVCpus

Since deploying the Nexus 1000v, it set our slot sizes in the cluster to 1.5GHz and 2GB of RAM. Not wanting to waste slots in our cluster by guests that may not reach that size (or partially fill slots), I wanted to carve out the cluster into slots of a lesser size, similar to using smaller block sizes on a drive to maximize space.

Using percentage reservations with vSphere, you can get by the slot sizes, but what if you’re starting a small cluster and growing it as resources are needed? How could I carve 25% out of a 2-node cluster? Sure, you can do it, but if you’re operating at the full 75% (with 25% reserved for failover) and lose a host, you actually don’t have enough resources and are over-committed by 25%.

Setting the following settings will help reduce your slot size, but may also have a negative impact by not having enough reservations if you end up in a failover state.

ESXi Auto configuration script

Lets face it, repetition sucks. When provisioning ESX hosts, using such things as the EDA make life easier, but it only does so much for ESXi.

The install for ESXi is simple and straight forward, but when done, you have to go and set everything else (IP, hostname, DNS, local users, etc…). Doing this for 20 hosts could be a PITA (Pain In The A..), so I set out on writing a script that does all of this for you.

All you have to do is set the IP & root password, then verify you can ping the host by it’s hostname (set host/A record in DNS). Once that’s verified, here’s what the script does for you:

Creates an Admins group and assigns it to the Administrator role
Creates local users, sets their default password, and adds them to the Admins group
Sets primary & secondary NTP & DNS servers
Sets DNS search suffix
Combines the provided hostname with DNS search suffix to populate the hostname FQDN
Sets EnableNaviReg to 0, disabled (requested by my storage team)
Disables iSCSI (disabled by default, but enabled in my sd image I created from previous post, thus the need to disable)
Disabled Tech Support Mode, aka ‘unsupported’ console

This is a slightly more advanced script, and it’s not fully polished, but works.

Dell’s Caption Contest Winner gets trip to VMworld 2010

Click here for more information.

Voting ends this Friday at 5pm CST and I’m currently in 3rd place. I’d appreciate any votes I can get, as I doubt my employer will send me to VMworld again this year.

If you view the leader board, mine are by “cougar694u” and the one I like most says “I told you we should’ve bought the m1000e filled with m610’s instead of this unstable UCS carp!”

I have a feeling the first two people have people gunning for them, as they’re growing daily, but it doesn’t hurt to ask, does it?

Using PowerCLI to rescan HBA and VMFS v2

I wanted to expand This Script to allow you to specify hosts as well, instead of just vCenter.

This came about because we have 20 new hosts that need storage so we can build our new vCenter server on them, and my old script wouldn’t suffice.

I know you can rescan at the container level (cluster, folder, datacenter), but sometimes the processes would hang on large clusters, other times I’d have to rescan twice. I like this script because it rescans all HBAs one by one, then rescans VMFS after. One could probably add the -runasync, but then it’s the same as the right-click in vCenter.

So, without further ado, here’s the updated script:

Finding WWNs for HBAs in multiple ESX or ESXi hosts, standalone or clustered

**Update May 07, 2012 – Use the new script here: Updated: Finding WWNs for HBAs in ESXi hosts, now with Get-VMHostHba

When building a new cluster, your storage team (or you) may need to add several hosts into the shared storage zone. It’s a pain to go to each host, configuration, storage adapters, then copy out the WWN.

With this script, you can supply a vCenter server and Cluster/Folder/Datacenter (any logical container) and it will list all the WWNs for Fibre Channel devices. But what if you don’t have vCenter stood up yet? No problem, you can also supply a list of ESX/ESXi hosts to scan.

Shawn & I built this because we have 20 hosts we need the WWNs from to provide to our storage team, and vCenter isn’t alive yet.

Our script:

Using PowerCLI to rescan HBA and VMFS in a cluster

Having an ESX cluster is nice, and adding shared LUNs can sometimes become click redundant (host, config, storage, rescan; repeat).

Since we’ve been migrating to a new storage array, we’ve been adding quite a few LUNs to different clusters on different vCenter servers, so I wanted an easy way to rescan everything.

So here’s my script:

Mass Storage Migrations using vSphere Storage vMotion and PowerCLI

We ran into an issue where we needed an entire SAN frame retired. Problem is, there are several datastores and several guests running on that frame.

I wanted to script it out, which worked just fine. Then, we had more to do, so I edited the script and ran it again. After the third or fourth time, I decided to write a script that takes params via the cli.

Make sure your datastore names are similar, for instance, mine appends ‘_New’ to the end. So my datastores have to be named like this: ‘vmdatastore’ and ‘vmdatastore_New’. It will get all guests on the datastore and migrate them one by one over to the new datastore. When done, just delete the old datastore (or rename it to _Old) and rename the new one to match.

My script:

Intel Nehalem EX & DDR3 Speeds

We all hate that adding DDR3 sticks to a server slows down the QPI speed (or RAM Bus for lack of a better example).

That changes with the Nehalem EX proc (and perhaps Westmere), as the CPU governs the speed. You can throw up to 16 sticks of DDR3 RAM per CPU at either 800, 978, or 1066MHz, and the governing factor is the CPU:

vSphere Maximum Configuration – VMs per host limitations on Update 1

When planning a new virtualization environment, consolidation numbers are always flying around, and specifically the number of VMs you can run on a host.

According to This Doc you can have a max of 320 VMs per host, but keep in mind the number’s different for HA clusters. I was also pleased to find out the numbers were slightly changed for Update 1.

Fast deployment of vSphere ESXi 4.0 running on a 1GB SD-Card

When we’re ready to deploy new ESXi hosts in our environment, we order them from Dell with ESXi pre-loaded on the internal SD-Card. This is nice and all, but what do you do when you have to go through and configure NTP, Users, Groups, Scratch directory, lockdown mode, and the list goes on?

You’d have to fire up each server, go through and configure everything, x10 if you had 10 new servers.

Since we’re working on a new rather larger virtualization deployment, we were looking at ways to overcome this.