SKT2
3 Zinc

number of available mset mirrors

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"The operation cannot be performed because the number of available mset mirrors would be exceeded"

i am trying to understand more on the limitation of the number of avaliable msets..
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xe2sdc
4 Germanium

Re: number of available mset mirrors

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When Solution Enabler issues commands against your box can use different syscalls with different parameters. Some of them needs the full list of symdevs to manage (split/resume/failover/failback/establish/whateveryouwant). Some other needs ranges of symdevs.

With SYMAPI_SYSCALL_RANGES_HEURISTIC you can enable "range syscalls" that will speed up command execution. But if you have a binfile with holes (non contiguous symdevs) syscalls may fail with strange and exotic errors. That's why you can always disable heuristic ranges and use good old "lists" of devices. Slower, but reliable ;-)
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MarcT2
2 Iron

Re: number of available mset mirrors

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It would be helpful to know what it is you're trying to do, and what the current device configuration is.

Each Symmetrix device has 4 "mirror positions". A standard mirrored device uses two of these (one for each copy).

SRDF uses an additional mirror position (on both the R1 & R2), so our device is now up to 3. Establish a BCV and all 4 mirror positions are used. This means a second concurrent BCV or RDF volume cannot be established, since there's nowhere for it to go.

A traditional hotspare also takes up a mirror position whilst invoked, so a mirrored RDF volume with a spare invoked cannot then have a BCV established since there is no free mirror position.

You can use "symdev show <Vol#>" to see what's in the mirror positions, you'll get something like:

Mirror Set Type : [Data,Data,N/A,N/A]

in the output.

Hope that's useful!

Regrads,
Marc
MarcT2
2 Iron

Re: number of available mset mirrors

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Hmmm...

Scratch the bit about "symdev show" - it doesn't appear to show the presence of an established BCV in the mirror set information.
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SKT2
3 Zinc

Re: number of available mset mirrors

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is there way(unix command is preferred) to check how many mirror positions are curently established if the LUN inumber is known? I need to run this when the problem reports.

This could be mostly due to a hot spare being invoked at that point in time since we never go beyond one SRDF/BCV copy.

But i need to confirm the presnce of a hot spare if that is the case.
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josevtome
1 Nickel

Re: number of available mset mirrors

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Found this thread looking for the same error message. Found that what MarcT replied is true. Now I have another question to add here:

If I have a volume in a failed disk, and this volume have already it's 4 mirror possitions occupied by SRDF, TF/Mirror operations, etc, can there be any problem while invoking the Hotspare operation?

Lately the Hotspare scripts are taking very long in my platform, 12+ hours to finish sync. Is this normal, or could the lack of mirror possitions be affecting this operations?
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SKT2
3 Zinc

Re: number of available mset mirrors

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i would say following flags determine them .

ms_spare_mir4, ms_allow_dynamic_mir and ms _smmf_std flags .

what is the size of the failed disk and what is the code version of the array?
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MikeMac1
2 Iron

Re: number of available mset mirrors

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If I have a volume in a failed disk, and this volume
have already it's 4 mirror possitions occupied by
SRDF, TF/Mirror operations, etc, can there be any
problem while invoking the Hotspare operation?


Symm devices only have 4 available mirror positions so if all 4 mirror positions are currently in use a hot spare will not invoke.

Lately the Hotspare scripts are taking very long in
my platform, 12+ hours to finish sync. Is this
normal, or could the lack of mirror possitions be
affecting this operations?


Reads and writes from the host take priority over a hot spare syncing. There are many variables as to why a hot spare could be taking a longer time than suspected to sync up. You mention TF/Mirror, are you also currently doing BCV operations at the same time that the hot spare is syncing?
mvs3
1 Copper

Re: number of available mset mirrors

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Looking for:
- A way to see / visualise how many mirror positions are in use.
- Clarification if TimeFinder Clone volumes occupy one of the 4 mirror positions (or not).
- Clarification if free mirror position(s) are needed to use SymOptimizer
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xe2sdc
4 Germanium

Re: number of available mset mirrors

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MVS first of all welcome to our support forums.

If you have a few spare minutes don't forget introducing yourself in coffee break area.. :D

1) a way to see/visualize how many mirror position are in use.

Just issue "symdev -sid XXX show 0BAD" and look carefully at the output. Unfortunatly I can't show you an example output but I guess you can easily spot the required details.
Or simply just post output of above command (assuming you want to know everything about your BAD device) and we'll help you in finding the details you need.

2) Clone won't ever use mirror positions. Fullstop. :-)

3) I guess MikeMac will happily answer with plenty of details ;-)
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Re: number of available mset mirrors

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According to emc94007 optimizer does use a mirror position.
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