Got a question about iSCSI Round Robin Multipathing and multiple extents. iSCSI storage is based on 3 Dell EqualLogic PS6000XV's. Storage volume is 15.13TB total that consits of 31 500MB extents. I can look at the main volume through Vsphere cleint and see that round robin is enabled. If I look at extent1, it shows round robin. If I look at extent2 and bleow, it shows me fixed pathing. Do I need to set round robin on each individual extent?
Yes you do.
Great.. Thanks for the quick reply.
If I had to make a guess, ESX will want to rescan the volume/extents after this change is made. Do the guest VM's need to be down for this change? I also have two other hosts in this cluster. Does the extent change need to be made on each host?
Changing the PSP to round robin does not require a rescan, but is a host by host option, so you will need to change it on every host.
Thanks for your help!!
FYI: Here's a script for ESXi v5, that will set all the EQL volumes to Round Robin and most importantly set the IOPs value to 3. The default value of 1000 doesn't result in efficient use of all links.
This is a script you can run to set all EQL volumes to Round Robin and set the IOPs value to 3.
esxcli storage nmp satp set --default-psp=VMW_PSP_RR --satp=VMW_SATP_EQL ; for i in `esxcli storage nmp device list | grep EQLOGIC|awk '{print $7}'|sed 's/(//g'|sed 's/)//g'` ; do esxcli storage nmp device set -d $i --psp=VMW_PSP_RR ; esxcli storage nmp psp roundrobin deviceconfig set -d $i -I 3 -t iops ; done
After you run the script you should verify that the changes took effect.
#esxcli storage nmp device list
Here's one for ESX(i) v4.x
Change to Vmware RR and set IOPS to 3
Script to change to round robin:
for i in `esxcli nmp device list | grep -i -B1 "ay Name: EQLOGIC" | grep -i "naa." | grep -i -v "ay Name"` ; do esxcli nmp device setpolicy --device $i --psp VMW_PSP_RR; done
Script to change the IOPS to 3:
for i in `esxcli nmp device list | grep -i -B1 "ay Name: EQLOGIC" | grep -i "naa." | grep -i -v "ay Name"` ; do esxcli nmp roundrobin setconfig --device $i --iops 3 --type iops; done