I have 20 Hosts, connected to two Different Storage Arrays, DMX3 and CX4, from 2 different SAN Switches in our Fabric, on DMX3 datastores, when I go to manage paths part, I see: 8 Active I/O, and the Path Selection is set to Round Robin, and in CX4 Datastores, I see: 4 Active I/O and 4 Active paths, and here the Path Selection is set to round robin as well, I'veI also requested Storage admins to use the ALUA protocol on CX4.
I just wonder, why again some paths are Active and not Active I/O.
and in DMX3, does it mean that all the 8 paths are used to send the I/O? (sure not concurrent).
Thanks for your consideration.
Many iSCSI arrays that have dual contollers are not really active active. So you get what you are seeing with those. Not real sure about the two units in question as I have direct experience with them.
If the CX is configured as ALUA then you have to set the path policy in VC to ROund robin then only the paths will say - Active I/O
By default ALUA is fixed.
For ex; on vsphere 5
esxcli storage nmp device set -d naa.asdfasdfasdfasdfasdfasdf1 --psp=VMW_PSP_RR
will set the device to Round robin