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2

Yes, this is possible. I know product recommendations are off-topic for this site, but several SAN appliance offerings are available for this. These days, I recommend: QuantaStor - Ubuntu-based. VMware certified. Has free and commercial variants. Uses ZFS under the hood. Excellent GUI. Zetavault - Ubuntu-based. VMware certified. Relatively inexpensive. ...


0

Have you checked the cable and port the device is plugged into? After that you will need to use the serial console to troubleshoot any further.


3

Your VMs will pause and say that there's no free space on the volume which the virtual machine(s) reside on. When a datastore runs out of space, thin-provisioned virtual disks can no longer dynamically grow to accommodate additional storage demand. When VMware ESX detects this condition, virtual machines in need of additional storage are instantly ...


3

By 'overbooked' do you mean overcommitted via the use of VMWare thinning? if so then what happens is that all reads stay good but any VMs that want to write can't - it's as simple as that, they get a SCSI 'block not available to be written to' error and have to deal with it however the OS/filesystem would do in that situation.


0

It depends on the model of your storage array; generally the volume will go read-only or off-line, which will cause interesting problems to your VMs. Primarily shutdowns, in my experience.


0

I have found the issue! The problem was in the networking layer between my hosts in the SAN. I first directly connect the SAN to a host and I did not have a problem. So I hooked it back up the way it was and started troubleshooting the networking. The traffic that this particular PS4000 SAN puts out is apparently adversely affected by Spanning Tree ...


1

edit: removed incorrect information So I'm seeing the EpIsoReason for port 16 is "NotLicensed". It also shows Licensed: False. I'm not sure why your show version command reported 20 licensed ports. The feature log command should display the true number of licensed ports- if that also agrees that it's 20 and these ports are still offline, then I'd open a ...


3

"well, technically it's possible, but it's not how we do it here" That sounds quite a lot like what I regularly tell developers ;) From an enterprise operational perspective you want as much as possible that applications use standard repeatable solutions. If your application doesn't need/warrant special treatment you're not going to get it. ...


2

If you're connecting several servers to a shared block device (DASD/SAN) you still need to either manually manage access to chunks of disk (some databases do that on raw disks, LVM is also an option, with managed LV access) or use a cluster file system, which will manage concurrent access. Even with write locks managed on a per-file basis, you might run ...


1

You need not just the shared hardware, but also a clustered filesystem. Regular filesystems wont work - two computers would end up overwriting each others changes, and you would end up with a corrupt filesystem. Clustered filesystems have the computers all notify each other about changes they are making, and handle locking files when needed so they don't ...


1

You don't want side effects from traffic disturb your SAN access. We have a small VMWare VSphere environment where we at first had both VMotion and iSCSI traffic going through the same switches on the same network. Different network adapters, but the same network. A bug in ESXi 5.0 made the hosts randomly lose access to the iSCSI SAN whenever a longer ...


6

Because not doing so allows regular traffic to impact on storage traffic, which is a bad idea as it means that say a user's download could delay an important read or write.


21

Because: Very, very bad things will happen if someone gains unauthorized access to your storage network Very, very bad things will happen if you have your iSCSI traffic not separated, and someone finds it a great idea to muck around with the STP topology at an edge switch, with the result of your entire network AND your storage subsystem going down at once ...



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