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clintonm9
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Dell EqualLogic Multipath (High IO throughput)

We have recently purchased a Dell EqualLogic SAN. Our main goal for this device was to start using resource pools and be able to do some HA and Live migration. We have been working with XenServer and Xen Cloud for a while and haven’t got the IO performance over iScsi that we were hoping. Using Multipath on the main Host machine we get about 250 MBps (Which we are happy with). On the Guest machines we will only get 120 MBps.

My question for the VMWare community; if we wanted to use the VMWare products is there the ability to get more then 1 Gbps IO throughput on a Guest machine? And if so, if there a PDF or a post somewhere that might explain how to do this?

Let me know, thanks!

Clinton

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DCasota
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I automated the configuration. Here the bash snippet (as you described it: must be applied on each host)

for i in `esxcli nmp device list|grep -i "Device Display Name: EQLOGIC" --before-context=1|grep -i "naa."|grep -i -v "Device Display Name"`; do

esxcli nmp roundrobin setconfig --device $i --iops 3 --type iops

done

(the line breaks seem to be a problem: write the "for" loop with the "; do" in one line)

Nachricht geändert durch DCasota

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depping
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Keep in mind there's a known issue with setting the iops from anything else than default:

http://virtualgeek.typepad.com/virtual_geek/2009/12/vsphere-4-nmp-rr-iooperationslimit-bug-and-worka...

Duncan

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DCasota
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Hi Duncan

Thank you for your advice. I just put one host in maintenance mode, did a reboot and checked the value. The iops value on each equallogic lun has changed to 1482662760...

The workaround - not to leave the iops value on the default value, but to start a post reboot script with the bash snippet (/etc/rc3.d/S99z_nmpfix.sh) - seems to work.

Daniel

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s1xth
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Depping...thanks for posting this information! I was NOT aware of this

problem when changing the iops setting under u1. I will have to test

this out after a reboot and see if it changes to a crazy number, I am

sure it will. Great information.

VMware really needs to fix these iscsi RR issues asap. Just another to

add to the list!!

Sent from my iPhone

On Jan 22, 2010, at 2:37 AM, depping <communities-emailer@vmware.com

http://www.virtualizationimpact.com http://www.handsonvirtualization.com Twitter: @jfranconi
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s1xth
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Just want to confirm, I rebooted my host with the iops setting changed to 3 and it also changed to a crazy number. Wonder when this is going to be fixed. 4.1?! Jeez... cant believe with how big iSCSI is used that this hasnt been fixed yet, along with the iSCSI drop issue.

Edit-- Even happens when your have the default 1000!! Jeez!!!!

http://www.virtualizationimpact.com http://www.handsonvirtualization.com Twitter: @jfranconi
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