Adding disks to ns120 performance question

how much capacity were you planning on buying ? As you probably know EMC Celerra is very particular to raid group design, certain raid group configuration while valid for regular open systems will not work with Celerra, it will simply not recognize them.

At the moment another TB would be sufficient but if we can get more capcity without decrading performance i would rather go for the 300gb disks options and get an addtional TB of space even if its at an addtional cost.

thanks

is it DAE 0_0 that has four empty slots ..at the very end right ?

yes correct, second shelf 4 slots right at the end.

cheers

anther question, why 300G FC drives ? You can get larger FC drives these days, i have 450G in my NS80.

so you have a couple of options

1) let's say you go with FC drives (300,450 ..whatever). You can buy 6 drives. One drive will become your new hot spare and go into one of the empty slots in DAE 0_0.  The other 5 drives will go into new DAE and configured in R54+1 configuration. This will ensure that when the space is discovered by Celerra, it will go into clar_r5_performance pool. Later one if you need more capacity, you can buy in 5 drive increments and keep populating that same DAE.

2) let's say you still go with FC drives. You can look at using 4+1 and 8+1 combinations (see picture). The problem with that is that 8+1 will end up in a different pool in Celerra. It's not a problem for new file systems but for existing file systems if you want to expand them in the future, you don't want them to span multiple pools (clar_r5_performance and clar_r5_economy)

3) How about SATA drives ? If this is truly for regular CIFS shares, SATA might be great for that. I have 150 terabytes of SATA in my NS80 serving thousands of concurrent users (students, staff, faculty). You can look in Celerra Monitor and look at disk performance during peak hours ..are you pushing your FC drives to the limit ?

You can right-click on the storage array (in my case, a CLARiiON) and get a variety of disk stats.

Thanks for your swift reply, at the moment our 146gb drives are FC so we will be going for the 300gb FC drives, personelly i think we went overkill on the spec. I think the option is to purchase 11 new 300gb disks, configure these as 2x R5 (4+1) RG’s and have one as a hot spare as the 146gb hot spare will not work with this RG?Correct me if im wrong?

Do you think this option is advisable? Will the celerra see this in the same r5 performance pool? And lastly (sorry for all the questions) does the 146gb disk have the IOPS capbilty as the 300gb disks?

Also lol where do i find "disk performance" in "Celerra Monitor"

Once again thanks for you help with this its much appreciated

Thanks

TTown wrote: Thanks for your swift reply, at the moment our 146gb drives are FC so we will be going for the 300gb FC drives, personelly i think we went overkill on the spec. I think the option is to purchase 11 new 300gb disks, configure these as 2x R5 (4+1) RG’s and have one as a hot spare as the 146gb hot spare will not work with this RG?Correct me if im wrong?

11 drives will work and yes ..you do need a 300G spare in that case

Do you think this option is advisable? Will the celerra see this in the same r5 performance pool? And lastly (sorry for all the questions) does the 146gb disk have the IOPS capbilty as the 300gb disks?

if you continue with this setup FC_RAID5_4+1_4+1_4+1 ..then yes, all LUNs will end up in the same r5 performance pool. 10k FC drives have ~140 IOPS, while 15k FC drives have ~180 IOPS. Obviously the 300G drive will have a lot more data on it and if all that data is actively accessed, then performance will be lower than a fully used and active 146G drive. For CIFS operations though ..i doubt you are reaching those IOPS.

excellent thank you, could you suggest some good reading material for navi manager? As i am a newbie to this, dont worry i will be booking the course sortly!

Thanks

all Celerra related documentation can be found here:

Home  >  Support  >  Technical Documentation and Advisories  >  Hardware/Platforms Documentation  > Celerra Network Server

good disk layout document

http://corpusweb130.corp.emc.com/ns/common/post_install/Configure_storage_Non_FC.pdf

Also, please rememeber to mark this discussion as "Answered" if you feel that your questionshave been answered>

glen

ok no problem

cheers