Vmware backup host limitation

[sumitgree]

Hello,

I have few queries related to vmware backup host limitation.

1) How many vmware hosts backed up through one backup host. I have not found any information related to vmware backup host in any dcoumentation ?

We are design a solution and need to identify how many backup hosts are requried for vms backup 

2)Can we use Proxy vm backup host  to mount iscsi LUN snapshot for backups ?

[sdo]

1) Depends upon the specification of the backup server, the versions, and the surrounding infrastructure.  And depends upon the backup target storage.  Best to refer to the performance and planning guide.

2) Be careful with the terms/concepts behind this question.  If you mean VMFS datastore LUNs via iSCSI then yes.  If you mean actual LUN snapshots using storage array technologies, then you need to be very careful and check the HCL.

[sumitgree]

I checked the performance and planning guide but i have not found anything related to vmware backup host planning 

[sdo]

The performance and panning guide is still relevant.

You have two possible infrastructure scenarios.  I can't know which, or whether both, will be applicable to your site.

.

1) Combined NetBackup VMware Backup Host + NetBackup Media Server (all on the one host)

...is a four stage process...

data producer - source storage array containing/hosting VMFS datastores

data consumer - NetBackup VMware Backup Host (i.e. the enterprise client side of things)

data producer - NetBackup VMware Backup Host (i.e. the media server side of things)

data consumer - target backup storage

.

2) NetBackup VMware Backup Host (i.e. a NetBackup Enterprise Client) is separate from NetBackup Media Server

...is a six stage process...

data producer - source storage array containing/hosting VMFS datastores

data consumer - NetBackup VMware backup Host (i.e. NetBackup Enterprise Client)

data producer - NetBackup VMware Backup Host (i.e. NetBackup Enterprise Client)

data consumer - NetBackup Media Server

data producer - NetBackup Media Server

data consumer - target backup storage

.

So, the thinking and planning is the same even though the transports my be different through each stage/hop/producer/consumer.

[Marianne]

My take on this is that everything depends on the size of the VMs and capabilities of NBU backup hosts as well as backup resources and backup windows.
Accelerator use will also influence backup performance which will determine number of VMs that can be backed up in a backup window.
Bear in mind that there is a recommendation to limit number of simultaneous backups from a datastore to 4. 
I have seen recommendation from users on this forum to limit this to 1.

There have been forum questions about number of luns that can be presented to a media server:

 VMWare Backup Maximum number of LUNS that can be presented to windows 2008 R2 

(More if you search this forum...)

If you want to use iSCSI for SAN transport, have a look at this user's experience:

ERR - Error opening the snapshot disks using given transport mode: Status 23 - iSCSI SAN  

Have a look at this Best Practice White Paper for NBU 7.1 - there may be some useful info: 

http://www.symantec.com/content/en/us/enterprise/white_papers/b-netbackup_best_practices_WP_21195951...

[sumitgree]

We want to use ISCSI to mount LUN on vmware backup host-Media server, Does using ISCSI to mount LUN is advisable or we have to avoid it?

Is there any challenge to use ISCSI to mount LUN on vmware backup host ?

[Marianne]

Have you had a look at the 2nd URL in my post above? The user is sharing his experience and how they got it to work. I have personally no experience with VMware and iSCSI as all of our customers are using FC SAN.