Do you have some feedback about Zimbra on iscsi storage (particulary Equallogic) ?

[allinbox]

I'm looking for some information to help me in sizing and best practices , Raid Level, kind of disk SATA or SAS ?

[Klug]

I'll answer here (and not on LinkedIn).

It depends on many factors : number of accounts (provisionned & active), number of mails sent/received, "bare metal" or VM, etc...

[dave_kempe]

yeah mailbox size and location of backups is also things you need to consider in sizing and choosing speed. we use iscsi and find its fine. Linux <-> linux only though.

[Klug]

One of their key features of Equallogic SANs, when you have several of them (SATA, SAS, etc) is the automagical balance of the data on different type of volume/disks depending on data usage.

This feature is directly integrated in ZCS, it's the HSM.

[Hatrix]

Whatever you do, make sure you have iSCSI initiator configured to queue if an error happens (you need multipath installed for that), I did not configure it at first and when you have a minor problem (network cable gets loose, whatever) you'l have to reinitiate the connection, which can lead to all sorts of troubles ...

in my case (as i use KVM machines which resides as well on the iSCSI, and inside the zimbra virtual machine another iSCSI connection to the mailstore) i had to reboot the KVM Host because reconnection did not work, or, reconnection did work, but the KVM's could not work anymore, they where frozen with I/O Errors.

So, make sure to test possible failures!