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nw 8.0 max nsrmmd count on shared DDboost devices
Hi everyone ,
I'm configuring a NW 8.0 server with ddboost devices , and I think that I have not fully understand the fields "max nsrmmd count" (on the device) and "dynamics nsrmmd" on the storage node.
the manual says :
In the Max nsrmmd count field, specify the maximum number of nsrmmd
processes that can run on the device. Use this setting to balance the nsrmmd load
among devices.
If Dynamic nsrmmds is enabled on the storage node, this value is automatically
adjusted by the formula max/target +4, with the default value being 14. Otherwise,
the default value is 4.
I've created one device on the server , and one device for every storage node , with the same path id / volume and so on .
so te same volume is mounted on the server + 14 storage nodes .
So (i think ) i must have globally spawned 15 nsrmmd over the datazone referring to the same device .
but if I print the configuration from nsradmin I've got :
nsradmin> show name ; max nsrmmd count ; current nsrmmd count
nsradmin> p
| name: \ |
"rd=devicename_DIR_ON_DD";
| max nsrmmd count: 4; | |
| current nsrmmd count: 1; |
on every ddboost device on the datazone .
I've also checked the manual but no further explanation .
anyone got a suggestion ?
CarlosRojas
1.7K Posts
1
August 30th, 2012 03:00
Hello Andrea,
Let's see if I can clarify for you:
max nsrmmd count means the maximum number of nsrmmd processes that a device will "support" or be able to run.
Bear in mind that the new functionalities of NW 8 includes a more B2D oriented architecture, so in other words NW 8 removes the limitation of tape device, where only one save OR restore could be ran at the same time.
With B2D and NW 8 you can configure the maximum number of nsrmmd (for either save or restore) that a device can run at the same time.
If you want to allow 4 save sessions and 4 restore sessions at the same time for a device (DD or AFTD), then you would be setting ma nsrmmd count =8 however the save sessions will always have priority over the restore sessions.
- Max sessions, target sessions and max nsrmmd count attributes will be adjusted to new defaults:
AFTD: TS = 4, MS = 32, MMD = 12
DD: TS = 6, MS = 60, MMD = 14
Also new configurations:
– Dynamic nsrmmds on NSR Storage Node resource
▪ Toggles dynamic provisioning on/off
– Max nsrmmd count on each NSR device
▪ Specifies maximum number of nsrmmd processes which will be started dynamically to handle requests to a device if dynamic nsrmmds is set to TRUE, and the number of nsrmmd processes which are started up front for a device when it is set to FALSE
▪ Recommended value based on formula (MS / TS) + 4
As for the dynamic or static nsrmmd's, that is only a matter of starting the nsrmmd's up front or being started as required per save/restore operation.
I think what you mentioned is that when configure one device, by default it will set to 4, but bear in mind that each storage node will have its own nsrsnmd and nsrmmd's running despite the device shows the settings=4.
You can check how many nsrmmd's are running on each Storage node that have access to that device.
If there are more devices, for testing purposes disable all other devices and leave only this one enabled for the storage nodes with access to it, and change the values you want, so you will see the number of nsrmmd's changing in the storage nodes.
Thank you.
Carlos.
CarlosRojas
1.7K Posts
0
September 11th, 2012 02:00
Hello Andrea,
Did this information helped to clarify?
Thank you.
Carlos.
lalexis
253 Posts
0
September 12th, 2012 07:00
Only 1 save or restore can be run at 1 time?
I am on 7.6.1 and can set my limits much higher, I regularly run 3 or more backups to the same tape at the same time as long as they are in the same pool it is not a problem.
Just set the target and max sessions on each drive
ble1
14.3K Posts
0
September 17th, 2012 04:00
With 7.6.x you can run one restore at the time (more correct way of saying would be you can run as much as you want, but only one read operation at the time will be active). In NW8 you can have multiple sessions.