• Please help support our sponsors by considering their products and services.
    Our sponsors enable us to serve you with this high-speed Internet connection and fast webservers you are currently using at ADSM.ORG.
    They support this free flow of information and knowledge exchange service at no cost to you.

    Please welcome our latest sponsor Tectrade . We can show our appreciation by learning more about Tectrade Solutions
  • Community Tip: Please Give Thanks to Those Sharing Their Knowledge.

    If you receive helpful answer on this forum, please show thanks to the poster by clicking "LIKE" link for the answer that you found helpful.

  • Community Tip: Forum Rules (PLEASE CLICK HERE TO READ BEFORE POSTING)

    Click the link above to access ADSM.ORG Acceptable Use Policy and forum rules which should be observed when using this website. Violators may be banned from this website. This notice will disappear after you have made at least 3 posts.

Replication - how should it be done?

droach

ADSM.ORG Senior Member
#1
Been reading up on replication and I am a little fuzzy on what is required and what is the best practice. For my first pair of source/target servers I am running SP v8.1.5 and using Directory storage pools. Using OC I defined the replication pair and I added the command 'REPLicate Node * Wait=Yes' to my daily schedule. All seems fine and replication and failover are working.
However, when I look at the details of my storage pool on my source server there is nothing set for 'Protection Storage Pool'. Without this setting I cannot use the command 'PROTect STGPool'.

So my first question is, should I be using 'PROTect STGPool' to replicate my pool, or is the way OC set it up OK?

For my second question:
Have a second pair of servers but these are running v8.1.6.100. On this pair I created a Cloud type storage pool on the source/target. This time, when I use OC to set up the replication pair I get the warning below. So, my question here is; why is OC warning me to use "storage pool protection" when it didn't set that up for my other server pairs?

1548948349331.png

Any guidance is appreciated.
 

marclant

ADSM.ORG Moderator
#2
First, it's important to understand the difference between protect and replicate:
- protect stgpool only protects the pool, it sends all the extents not previously protected to the other server. So, with this, you can repair your storage pool if you need to, but you cannot restore nodes from the target server.
- replicate node does two things, it sends extents that are not previously protected to the target, and it also sends the metadata to the target. So after replication is completed, a node could restore from the target

So in short:
- protect only data
- replicate data + metadata

The preferred method is to run protect first, followed by replicate node. That's because protect is more effective at moving the data to the target. Then when you run the replication, it only has to handle the metadata. So protect+replicate normally run quicker than if you let replicate node handle it all.

I don't have an answer for your 2nd question, I'd have to research, but no time to do so today. I may come back to it later.
 

droach

ADSM.ORG Senior Member
#3
Thanks for the explanation Marclant. I updated my source storage pool with the name of the pool on my destination server and kicked off a 'Protect Stgpool'. I also added the command to my Daily Task schedule, just prior to the 'replicate node * ' command.
 

DavrosDalek

Active Newcomer
#4
@droach would it be possible for you to share your commands you are using to both protect the stgpools and nodes in your daily script/schedule please ? I'm in the same boat as far as your fist question, your dialogue with @marclant has helped me but it would be nice to see your commands if that would be possible ?

Kind Regards
Craig
 

droach

ADSM.ORG Senior Member
#5
I recently met with an IBM 'Spectrum Storage Technical Specialist' and he confirmed what marclant said. Run 'Protect STGP' first, followed by 'replicate node'. The commands I use in my daily schedule are:

PROTect STGPool YOURPOOLNAMEHERE Wait=Yes
REPLicate Node * Wait=Yes
 

Rigido

ADSM.ORG Senior Member
#7
Interesting discussion, I will add few questions:
I set up a replication environment and just did node replication, source pool is a VTL 7650 and destination pool is a container pool:
  1. Is it possible to estimate speed increment for replication operations moving from a "replication" config to a "protect + replicate" config?
  2. I used nodegroup to split production nodes from test/quality/dev ones, all of them write data on the same pool (ORA, SAP, etc), should I split data pool too?
  3. Can I switch from "just replication" to "protect + replica" config or should I start from scratch?
Thanks.
 

marclant

ADSM.ORG Moderator
#8
Is it possible to estimate speed increment for replication operations moving from a "replication" config to a "protect + replicate" config?
You cannot protect, protect only works if the source and target are both using container pools, you can only replicate in your case.
I used nodegroup to split production nodes from test/quality/dev ones, all of them write data on the same pool (ORA, SAP, etc), should I split data pool too?
It depends. From an SLA perspective, if you need some nodes to be available before others on the target, it may make sense to replicate those first. If you don't have SLAs, then it's much simpler to replicate all the nodes. If you don't need/want to replicate certain nodes, update those node with "replstate=disabled".
 

Advertise at ADSM.ORG

If you are reading this, so are your potential customer. Advertise at ADSM.ORG right now.

UpCloud high performance VPS at $5/month

Get started with $25 in credits on Cloud Servers. You must use link below to receive the credit. Use the promo to get upto 5 month of FREE Linux VPS.

The Spectrum Protect TLA (Three-Letter Acronym): ISP or something else?

  • Every product needs a TLA, Let's call it ISP (IBM Spectrum Protect).

    Votes: 12 15.8%
  • Keep using TSM for Spectrum Protect.

    Votes: 48 63.2%
  • Let's be formal and just say Spectrum Protect

    Votes: 9 11.8%
  • Other (please comement)

    Votes: 7 9.2%

Forum statistics

Threads
31,352
Messages
133,541
Members
21,475
Latest member
sag
Top