raid type?

itdaddy

hey guys
what kind of commands can I run on a linux kernal
to see what the raid type is being used vs having to reboot the entire system

this linux kernal is a vm machine ESXi 3.5

does anyone know of a command how how to tell what raid type is being used???
thanks

/pub/beer/

itdaddy wrote: »

hey guys
what kind of commands can I run on a linux kernal
to see what the raid type is being used vs having to reboot the entire system

this linux kernal is a vm machine ESXi 3.5

does anyone know of a command how how to tell what raid type is being used???
thanks

This doesn't really apply to a VM machine, but I thought I'd put the full answer in case anyone else stumbles on the thread. Are you sure you even are using RAID? With the VM you'd have to have 2 storage disks and use software RAID. However there is no real purpose on running software RAID on a VM. If this is just for learning the commands, then forget my little rant

Hardware RAID? You'd need to know the vendor and have the respective utility or script installed to query the controller.

Software RAID? If you installed the machine using software RAID you would use the command "mdadm -D /dev/md0" for details the RAID device (/dev/md0). "man mdadm" for all the options, query might be another useful one.

itdaddy

yeah there are 2 disks....I just dont want to reboot the vm machine since we have so many servers on it. I am 75% sure it is raid 1 mirroring.

I didnt want to have to reboot to look at raid utility. Thought maybe I could use some linux command on the box to see it and verify it.
thanks man!

bdub

Do you know what size drives are in there? If so just use the VI Client to see how large the datastore is and from that you can determine if its 0, 1 or 5 etc...

itdaddy

they are 500 GB each I believe and the raid store is only 500GB
you would think it is raid 1 why would someone make raid 0 for a vmstore?

I can shut it off and turn back on but it take a while for all the servers to come up. it is a production server
you see I had built an exact twin machine same hard ware excatly.
I want to run the twin machine with the raid 1 drive to see if I have any issues with the new machine? like say maybe I have to reconfig the nic card?

bdub

Well if the drives are 500gb and there is only 2 of them and the datastore is 500gb than its configured in mirror mode RAID 1.

I am not sure if I understand your last part there about what you are trying to accomplish with your 'twin' machine.

Mishra

Look for software provided from the vendor you use that can be installed on Linux.

Example:

Dell has a Server Administrator made for Linux.

itdaddy

bdub
what I have is I bought an exact replica vmmachine as far as hard ware goes.
I mean I have two servers that have the exact same hardware: cpus, mobo, raid configuration, nic cards, chipsets etc... so when the mobo or cpus fail (if they do) then I can turn off the vmachine1 and take out raid set and put in standby twin machine turn it on and bam presto in 20 minutes later we have a failover that only cost me 3400.00 USD and 20 minutes of wait time vs 90K USD SAN system. wallla!!!! 20 minutes of downtime is nothing we had power outages lasting 2 hours before so this 20 minutes of downtime is nothing
since we are not that large in size, I use this type of failover system to save our main bread and butter services from completely failing.

bdub

Have you tested this yet? I would be sure to test this scenario on the weekend or after business hours and be sure that if you swap the drives into the other machine that everything will work they way you plan.
One thing thats great about VM's is that you can just copy the files for the VM and put them wherever you want and boot them up. If you are running ESXi you really don't even need to swap out the drives, just put ESXi on both machines, make copies of your VM's on a daily/weekly basis and put them on your failover server. This way you don't need to swap anything you just boot the VM's on the failover server and you're good to go.

This would be a simpler solution and will also cover you in case one or both of the drives fails in your primary machine.

itdaddy

bdub
yep I thought your idea was good to copy vms over to failover system. an regretfully I have not tested them yet. But in januray 2011 I plan to test them
to make sure all is well. and backing up the server is a must and putting them on the vm waiting to be used is a smart idea and trying to keep them uptodate and testing them yes will do and let you know how it turns out. butu t his was my option since we are smaller credit union and do not want to spend 100K on a SAN system of which I wouild love but would be over killl really and then we would have to havea backup system in place case the Corporate branch office be destroyed by fire or natural disaster. another 50 to 100K there.. yikes!