I have out primary fileserver which currently has 2 - 2TB vmdk's - both are set to independent. This is because when they weren't set this way vmware wasn't commiting the data to the extra disks it was writting/caching them to the Lun that had the vm's OS disk. So I made them independent but from what I've heard I can't do a VCB with them this way. I was hoping to do a file level backup of the disks using VCB as at this point we are actually using over 1TB on each disk and using a backup agent on the vm itself can take a long time, especially when doing a backup over the network. Any suggestions are greatly welcome, I did hear of a way to allow the vm to directly see the SAN tape system, which is a MSL 4048 and a HP VLS both are on FC along with the EVA the vm's are running on.
I'm acutally working a simular issue at the moment. The only ways I have found so far is if you have a backup setup / software that can talk directly to the SAN.
Another option is possibley Symantec Backup Exec 12.5's AVVI agent which allows you to backup image level files by using Vmwares API calls. This agent can acutally do this without a VCB setup, however it speeds things along if you can have backup software on the VCB server. It also allows you to do GRT restores of individual files from the image level backups however this does require a staging area to do the restore. Meaning if you have a 1TB image file you need 1TB of staging room to extract 1 file out of the image.
The only other way I have found and I'm still working on the details / best practices is if you the right switching network to do etherchannel and setup your ESX with IP-hash to get 2gb worth of bandwidth from the VM's on the ESX server, however as it seems each session will only grab 1 GB i'm still working on the details if its possible to get a full 2GB out of ESX without going to a 10GB nic / switch.
The one thought is to use the new FC NPIV, which I am using in my environment anyway. I could zone it to the tape drive, etc, (I'm the SAN guy as well as VM) But from what I've heard it isn't supported. And from what I've seen on the forum's is slow although I don't know how slow (probably because it's a software implementation of NPIV. I have a 4gb FC SAN network which would be a lot better to do the backups with then the standard ethernet network (1gb) we need to do at least an incremental almost everyday and a full at the end/beginning of the month. I may play with the NPIV but I can't use it if it's not supported by vmware.
NPIV will only work with DISK devices not tape devices at this time. CHeck out www.boche.net for some very interesting and useful information on using NPIV.
Edward L. Haletky
VMware Communities User Moderator
Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.
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