EVA4400 Vdisks

 
ET2
New Member

EVA4400 Vdisks

Hello, 

on EVA4400, we have some Vdisks that are presented to machines that are non existing anymore. or might be presented to a machine that has been renamed, and we THINK it is not existing anymore.

1. is there a way to read the data off those vdisks?

2. can we present the same Vdisk to two hosts at the same time ?

3. enlarging a Vdisk from 500GB to 600GB, is there anything that we need to check (other than the 100Gb is actuallly available) and will it interupt the machine utilizing that Vdisk ?

 

Thank you 

2 REPLIES 2
Torsten.
Acclaimed Contributor

Re: EVA4400 Vdisks

What OS on the servers?

If 2 servers accessing a non-cluster filesystem at the same time, you may corrupt the data within seconds!


Hope this helps!
Regards
Torsten.

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Sheldon Smith
HPE Pro

Re: EVA4400 Vdisks

An EVA is a block-storage system, and not a file-storage system. It creates volumes (Vdisks) which are then presented (LUN) to one or more hosts. The file system is defined by the host. All the EVA knows is <LUN number/Block location/IO size>,

To read a "strange" Vdisk, first you need to know what file system was written (and quite possibly what operating system wrote it); you will need that to read it.

Second, as Torsten wrote, if two hosts access a vdisk and they are not clustered, then each has no idea what the other is doing and will quickly corrupt the volume as seen by the other. You either need to track down one of the systems that is still "alive" and check the volume from there, or, unpresent the volume from all systems and then present it to a known host.

To summarize to your questions:

  1. You need a host that understands the file system written on the Vdisk.
  2. Only if the two hosts are part of the same cluster.
  3. Check whether or not the operating system's file system allows volume expansion. In years gone by, some hosts would simply ignore the fact that the underlying volume was expanded. Other hosts would actually crash if the underlying volume changed size.
    I think all "modern" operating systems and file systems now handle volume expansion. However if you do not know, check first.

 

Note: While I work for Hewlett Packard Enterprise, all of my comments (whether noted or not), are my own and are not any official representation of the company.
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