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Allen_Ward
4 Ruthenium

DSE on VMAX3

I'm digging through documentation trying to find the right way to activate DSE for RDFGs on a VMAX 400K that replicates to a VMAX 20K. I seem to be finding a combination of conflicting and incomplete information on the formatting of commands for the VMAX3 side of things. Is there any documentation anyone is aware of that is specific to this situation?

There is a LOT of info out there for this (and I have experience with this) on the VMAX2 and earlier arrays, but the VMAX3 does it different and it isn't clear to me what will and won't work. I really need to know this before I start trying it out as I have no test environment.

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KW160
2 Iron

Re: DSE on VMAX3

On the VMAX3 and All Flash series of arrays, there are three operations that relate to DSE:

1. Enable the SRP to support DSE. (This will be defaultly enabled on the Default SRP)

2. Set the dse_max_cap setting to limit the total size of the DSE.

3. Enable "autostart for DSE" on the SRDF group. (Defaultly on for VMAX3/AF)

These operations are described in the documents below:

EMC™ Solutions Enabler Array

Controls and Management

Version 8.3

CLI User Guide

Solutions Enabler SRDF Family

Version 8.3

CLI User Guide

Allen_Ward
4 Ruthenium

Re: DSE on VMAX3

I've been through both of those documents, but it doesn't seem to call out clearly the process for just the VMAX3 side of things. It might make sense if you already know the answer, but figuring out what they mean the way they word it isn't the same thing *lol*

Thank you and I'll be putting this into my playbook for later this week. Hopefully this is everything I need for this end of the link.

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zzanne
1 Nickel

Re: DSE on VMAX3

Are you looking to activate it or modify it?  Is it different depending on what array you are replicating to?  I know my 100K is enabled by default (which I found out only because of a large data dump over a smaller link).

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Allen_Ward
4 Ruthenium

Re: DSE on VMAX3

I was trying to set it up, but it does appear that it is set up automatically. I've been able to modify that max SRP capacity used by DSE but there are still a lot of gaps with VMAX3.

EMC Engineering recommended that I drop the default spillover threshold from 50% to 40% but none of the commands to do that appear to work. I also can't find any way to monitor DSE usage in the SRP to determine if DSE was actually used. For my VMAX2 arrays I can see this under the Performance tab where I can chart the DSE pool utilization (% full). For VMAX3 I haven't been able to find a similar setting.

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KW160
2 Iron

Re: DSE on VMAX3

You should be able to see the DSE capacity in use with this command:

symcfg -sid xxx list -srp -detail -v

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zzanne
1 Nickel

Re: DSE on VMAX3

Current use also is available in U4V in the dashboard. In the SRP section in the middle, just change the dropdown to SRDF DSE Allocated.

You can see *some* history in U4V, but my screen doesn't quite have the options the help tells me about.

I can see tracks used per storage group and adjust the time frame. My copy/paste does not work in the web so hopefully I type this right.

Performance Mgmt > Anaylze view > Trending and Planning - Views > Trending and Planning - Data Protection > DSE Pools view (Trending and Planning).

I don't have DSE Pools, but I have SRDFA which shows me tracks used.

Hope that helps a bit.

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Allen_Ward
4 Ruthenium

Re: DSE on VMAX3

Thanks for that, but it only let's me know if DSE is in use at the exact moment I issue the command. I'm looking for a way to see if DSE was used in the past day or week or so. Normally I could get that out of a performance chart in UfV.

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Allen_Ward
4 Ruthenium

Re: DSE on VMAX3

I found it. I was looking for something specifically calling out DSE. Not to find it buried in another set of metrics.

mscheuer
1 Copper

Re: DSE on VMAX3

What metrics did you find?

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