How many EMC gatekeepers do I need? 1

[StuartA46]

I have one EMC 8430 with 5 big UNIX servers. 82 disks. 407 Hypervolumes, split almost equally to 5 UNIX HP servers. How many gatekeepers should I present to each server? One per server? Are there guidelines for this? What manual do you look this up in?

Stuart

 

[hammo]

I normally use a rule of thumb of one gatekeeper per DG that is using SYMCLI options. For example if one of the servers had 4 DG's each performing TimeFinder commands I'd have 4 gatekeepers for that server. That way you never end up with conflicts.

 

[StuartA46]

Hammo:

I hear you and thanks.

Somebody told me that I should have one GateKeeper dedicated per server. What do you think of that?

 

[wardy66]

It really depends on what EMC software you're running on each of the servers.

Remember, a gatekeeper is a path from the server to the Symm. You need to think what information needs to flow between the two.

 

[liamfogarty]

I agree it depends on what the server is running.
If the server does not use any symcli etc commands then there is no need for any gatekeepers.
But on the other hand, If you have a mangement console that should have several (i.e.4-6).
But for a normal server that will just be using it for establishing bcv's etc..(normal stuff) then 2 gatekeepers is loads.

Liam

 

[Chacalinc]

Hi folks!

All EMC software (TimeFinder, SRDF, SDR, etc.) run IN the Symmetrix, so servers (with SYMCLI or ECC) only issue commands to the Symmetrix and Symmetrix perform the job internally. The problem is that Symmetrix boxes can not assign memory for software, only devices, so (cleverly) EMC creates tiny devices of 6 cilinders (aprox. 2,88 MB) in order to give the requiered memory IN the Symmetrix, so symm box can receive the commands from symcli/ECC through gatekeeper devices (to the symmetrix memory) and perform it.

Now, with servers where NO EMC software is running, you don't need gatekeepers. In servers, where EMC software is running, the quantity of gatekeeper will depend on how many "device groups" you will have. If you are running i.e. timefinder and SRDF, in a device group you will use the SAME gatekeeper in order to run timefinder and/or SRDF commands with the same device group.

With several servers running EMC software, it is recomendable to use different gatekeepers, just to avoid issuing command to the same gatekeeper at the same time.

Hope this help you.
Cheers.

 

[wardy66]

If you're using EMC ControlCenter, then the rules are quite simple. This is from the Performance and Scalability Guide.

For each Symmetrix system connected to a host:
- Two gatekeepers are required when the Storage Agent for
Symmetrix is installed on the host and two (total of 4) additional gatekeepers are required when you use Symmetrix Configure commands to manage the Symmetrix system.
- No additional gatekeepers are required for any other
ControlCenter process except when a Host Agent is installed in the absence of the Storage Agent for Symmetrix. In this case, one gatekeeper is required.