VM + Application consistent mode: Need scAgent?

[chao]

Hi Gurus

By my experience about snapcreator,  I always install scServer and scAgent in difference server.  if the application is at same server with scSever,  scAgent is unnecessary.  only scServer is OK. am I right?

When I try to deploy a  VM + Application consistent mode, ( the application MaxDB is in a VM,  I also install scServer in same server),   I was request twice times to enter Agent.

the first time is for VC (I guess, because it's before enter application setting).  I could skip it. but 2nd time, it said the Agent IP is required. 

then I have to re-install the SC to include the Agent.  but unfortunately the scAgent service could not be startup normally. (how to troubleshoot?  I did not find any logs except windows event).  I plan to manually remove the Agent setting from the conf file.  Does it make-sense?

Your advice is appreciated

[Arora_Kapil · Accepted solution]

Hi,

You will need both server and agent for vm+app backup but on different machines

1) Server outside of the vm you are taking backup for

2) Agent within the vm to take care of MaxDB quiesc and un-quiesce.

When you start creating the config, you can leave the first agent blank but you need to give details of the agent inside the VM where MaxDB is installed for the second agent.

Let us know if it works.

Thanks,

Kapil

[chao]

Hi Kapil

Thank you very much. Because customer has no more "free" server for dedicated server,  before I talk with them, I have several questions

1) could Server and Agent stay at same server?  is it a supported architecture? during the installation, I could select them both. 

2) if keep server and agent in same sever, is there any special setting?  It's very strange,  I could not start-up Agent

3) I try to manually empty the agent setting in #####_maxdb_1.conf ,  I roughly trigger a backup and it works.  but I am not sure what's the impacting.

BTW, there are four configuration under the profile. what't the purpose?

maxdb1 - > I guess it should be main configure to call all others

maxdb1_maxdb_1  -> I guess maxdb1 will call it to handle maxdb

maxdb1_restore -> what's for?  only for restore.  (in my case, the datastore is FC-SAN which is dedicated for this maxdb)

maxdb1_vibe -> what's for?

[Arora_Kapil]

Can we have a chat about this over phone? I would like to explain to you how vm+app works.

You can send me an email at kapil.arora@netapp.com

Thanks,

Kapil

[Arora_Kapil]

VM + App backup is actually a VM backup which is app consistent.

To take a VM backup you cannot install a SC server inside the VM itself (for which you are taking the backup).

And to make sure that MaxDB is consistent and to perform quiese and unquiese operation on it you would need an agent inside the VM as MaxDB is inside the VM.

So you definately need both agent and server.

maxdb1 - >yes we call it master config

maxdb1_maxdb_1  -> This is a plugin config which has agent and max db info, this is pulled for quiesce and unquiesce operations on MaxDB

maxdb1_restore -> This is to perform a restore, restore is just a VM restore and this is just a vibe config to do that. No MaxDB related operations are performed during restore.

maxdb1_vibe -> Ths is vibe plugin config, this takes care of vibe quiesce and unquiese operations.

These are the steps called by master config

1) Vibe auto discovery

2) maxdb quiesce

3) vm quiesce

4) backup snapshot

5) vibe unquiesce

6) maxdb unquiesce

Thanks,

Kapil

[chao]

Hi Kapil

Did I misunderstand anything?  how should I use the configuration: maxdb_restore?  It will be called by Q81 or I should directly use it to do restore? when I try to use the configuration maxdb_restore to do restore operation.  but it reported "unable retrieve snapshot list".

thanks and best regards!

TC

[Arora_Kapil]

Hi,

You will need to run discovery operation on your restore configuration first.

Currently restore configuration does not contain the volumes details and so it is unable to find the snapshots.

Thanks,

Kapil

[chao]

OK. I did

but if I want to do a restore,  which configuration should I use?  maxdb  or maxdb_restore?  I tried to use maxdb and it works. but I want to know if I miss anything.

[Arora_Kapil]

1) maxdb config is the master config, it will not perform vmware restore, If I remember it will open the normal SC framework restore wizard.

2) maxdb_restore is a vmware config and will perform vmware restore which is app defined restoreimplemented in the vibe plugin.

Thanks,

Kapil

[chao]

Hi Kapil

thanks a lot.

Yes. I tested master config,  it will give a prompt volume restore or SFSR.  because my scenario is to use dedicate volume/lun/datastore for this VM. so master config should work too.

I did not test maxdb_restore yet.  according my testing before, to use VIBE plug to do single VM restore for SAN will trigger a VMware copy file operation, it's a little slow but safe for shared datastore.  I will test when free and reply you.

thanks and best regards!

TC

[chao]

BTW,  To use VIBE plug to restore a VM at VMFS datastore will do

1) clone a lun

2) ESX connect the cloned lun as datastore

3) VC start a copy file to copy related file from cloned datastore to real datastore.

I found at least during the file copying,  even the original vmdk is thin-provision, but it will still occupy claimed size capacity.  so my restore is failed because real datastore has no enough space.  is it make-sense?   any advice and idea about that?