by Duncan Epping
Another update again by Rob de Veij, RVTools 2.4. This release includes a new feature, filtering. Rob also revealed that the upcoming version will contain health checks. Here are the changes:
Version 2.4 (March 2009)
Now head over to Rob’s website and download the new version!
When I started out with ESX 3.0.x the first thing I wanted to do was disable the VMFS-2 driver. There’s no need for it when you’re not accessing VMFS-2 volumes and removing it can lead to performance gains or at least a faster rescan of your storage. Removing it, according to to this section of the VMware website, was supposed to be really easy:
vmkload_mod -u vmfs2
Unfortunately, this just unloads the module and every time the server gets rebooted the module is loaded again. Same goes for the esxcfg-module command, it unloaded it but after a reboot the module was loaded again. You could add the command to /etc/rc.local of course. This would unload the module every time the server booted. I’m not a big fan of manually changing files like this, and luckily as of the next generation of ESX(vSphere) this doesn’t seem to be necessary anymore:
esxcfg-module -d -d|--disable - Disable a given module, indicating it should not be loaded on boot.
The funny thing is when I run the “esxcfg-module -l” command it still lists the module as loaded. If I run the “esxcfg-module -q”, which only queries the enabled modules, it’s not listed. After a closer investigation I noticed that the following line changed in “/etc/vmware/esx.conf”:
/vmkernel/module/vmfs2/enabled = "false"
I did a cross-check, it’s most definitely not loaded. Cool, remember this one “esxcfg-module -d”. It will come in handy some day.
Your VMFS has been recognized as a snapshot, what are you going to do? Hopefully most of you have read my previous post on this topic by now. If you didn’t, be very ashamed and start reading my EnableResignature post before you continue.
I was just playing with a VMworld Europe lab manual, which was about the next version of ESX/vCenter(Part of vSphere). I noticed the following new command on the command-line: esxcfg-volume. I did a help and the following showed up:
-l | --list -m | --mount <vmfs uuid|label> -u | -- umount <vmfs uuid|label> -r | -- resignature <vmfs uuid|label> -M | --persistent-mount <vmfs uuid|label>
As you can imagine this command will come in handy when a VMFS/LUN is being recognized as a clone or snapshot! With version 3.5 you needed to change an advanced setting. This setting wasn’t specifically for just one LUN, but for all of them, which is a risk. With the next version of ESX you could do the following if a volume has been detected as a snapshot and you want to resignature it:
esxcfg-volume -l
esxcfg-volume -r 49ba276a-c9e135b6-26f8-000c29123ede
Or if the current cloned volume isn’t connected you could also just mount it:
esxcfg-volume -l
esxcfg-volume -m 49ba276a-c9e135b6-26f8-000c29123ede
And if you are absolutely sure the cloned volume will not return you could mount it persistantly, which is the equivallent of “EnableResignature=0, DisallowSnapshotLUN=0”:
esxcfg-volume -l
esxcfg-volume -M 49ba276a-c9e135b6-26f8-000c29123ede
Don’t you just love this new exciting command-line magic! There’s more to come over the next days/weeks.
btw: there’s also a way of doing this from the GUI… Just add a new LUN, select the LUN that you want to mount, depending on what needs to be done pick “Assign a new signature” or “Keep Existing Signature”. But where’s the fun in that?
I’ve been playing around with powershell yesterday. We needed to create over 100 VM’s and there’s no point in doing that all by hand. The customer provided us with a .csv file that contained specific info on these VM’s. It took me a while to figure out how to read the info.csv file and how to actually use it. But as always it’s actually fairly simple and that’s why I decided to write it down:
Before we even start, the CSV should be formatted as follows:
vmname,cluster
VM001,HA-DRS-Yellow-Bricks
Read the complete csv file into a variable:
$csv_info = Import-Csv c:\scripts\info.csv
For every line in the csv variable do something:
foreach ($line in $csv_info) {
write-host " This is virtual machine $($line.vmname) on cluster $($line.cluster)"
}
This line would print something like this:
This is virtual machine VM001 on cluster HA-DRS-Yellow-Bricks
As you noticed in the example above we used $line.vmname to get the name of the VM printed and $line.cluster for the cluster name, cool huh! BTW, Alan’s quick reference guide really helped me out!
Before anyone starts shouting, yes I’m a VMware employee and a VMware fanatic or whatever they call it these days.
One of my customers phoned me up today and wanted to discuss the fact that XenServer Enterprise is available for free. I wasn’t prepared at all which makes a discussion like this very “interesting” to say the least, especially because I’m not a competitive expert.
I answered the customers question by asking a question: Do you really think the product is free and enterprise ready?
The customer referred me to this blog article by Mr. Crosby, the article clearly states:”…will find in XenServer a complete free Enterprise Virtual Infrastructure solution”.
This particular customer is a heavy DRS user, I’m talking about multiple clusters with each at least 3 resource pools which contains at least 100 VM’s each. The current version of XenServer doesn’t have the DRS implementation the customer currently uses, but not only doesn’t the current version have this feature… the next version will also not have this feature. DRS will be part of Xenserver Essentials, in other words the paid management tool.
I’m just a consultant, I might be wrong… but most of my customers consider DRS to be an Enterprise feature. But it’s actually not only DRS that’s missing from the Free “Enterprise” Virtual Infrastructure solution… what about High Availability? I could be wrong again but all my customers seem to agree that High Availability is an Enterprise feature. Again HA is available, but it has been shifted from XenServer Enterprise to XenServer Essentials, yes the paid version… and what about support on the Free version, can’t seem to find any info on support.
Now I’m not going to tell you guys that VMware has the best product or that XenServer doesn’t cut it in an enterprise environment because that depends on your needs and wants. I do want to stress that not everything is what it seems to be and don’t believe everything you read.