HI<\/p>\n
is there any benefit of having multiple targets created from a same disk pool?? i got 45 TB disk pool which i am planing to create one iscsi Target and assign it to 5 different host.<\/p>\n
and will this effect if i want to create a sever cluster in the future ?? (Multipath i/O)<\/p>\n
any advise please?<\/p>","upvoteCount":8,"answerCount":3,"datePublished":"2018-04-16T13:12:23.000Z","author":{"@type":"Person","name":"donarachchi2","url":"https://community.spiceworks.com/u/donarachchi2"},"acceptedAnswer":{"@type":"Answer","text":"\n\n
<\/div>\n
donarachchi2:<\/div>\n
\nHI<\/p>\n
is there any benefit of having multiple targets created from a same disk pool?? i got 45 TB disk pool which i am planing to create one iscsi Target and assign it to 5 different host.<\/p>\n
and will this effect if i want to create a sever cluster in the future ?? (Multipath i/O)<\/p>\n
any advise please?<\/p>\n<\/blockquote>\n<\/aside>\n
The answer is - it depends. Depends on what you use on a server side and on clients as well. Say MSFT target can’t scale well with multiple iSCSI sessions so increasing number of vLUNs having few iSCSI sessions / vLUN helps. Same about client - MSFT has issues with ~400K IOPS per LUN on client<\/strong> so having multiple vLUNs helps again. Linux / FreeBSD are different.<\/p>","upvoteCount":0,"datePublished":"2018-04-16T17:26:21.000Z","url":"https://community.spiceworks.com/t/multiple-iscsi-targets/646378/3","author":{"@type":"Person","name":"kooler-starwind","url":"https://community.spiceworks.com/u/kooler-starwind"}},"suggestedAnswer":[{"@type":"Answer","text":"HI<\/p>\n
is there any benefit of having multiple targets created from a same disk pool?? i got 45 TB disk pool which i am planing to create one iscsi Target and assign it to 5 different host.<\/p>\n
and will this effect if i want to create a sever cluster in the future ?? (Multipath i/O)<\/p>\n
any advise please?<\/p>","upvoteCount":8,"datePublished":"2018-04-16T13:12:23.000Z","url":"https://community.spiceworks.com/t/multiple-iscsi-targets/646378/1","author":{"@type":"Person","name":"donarachchi2","url":"https://community.spiceworks.com/u/donarachchi2"}},{"@type":"Answer","text":"
What kind of hosts do you plan to assign it to? You can only assign a LUN to multiple hosts if they are clustered, or if they are VMware ESXi. Most other cases will corrupt your data.<\/p>\n
My rule of thumb is to leave enough free space on storage to fully clone whatever your largest object is. For a SAN, that means being able to fully clone the largest LUN. For a hypervisor with local storage, keep enough free space to be able to make a copy of the largest VMDK or VHDX somewhere. There are flexibility benefits of using smaller LUNs, and some performance benefits as well. I prefer to keep LUNs under 2 TB, even if I have 45 TB of available storage.<\/p>\n
Note that SAN arrays also need free space for snapshots and normal operations. You should get alerts when your array gets close to full.<\/p>","upvoteCount":1,"datePublished":"2018-04-16T14:26:54.000Z","url":"https://community.spiceworks.com/t/multiple-iscsi-targets/646378/2","author":{"@type":"Person","name":"kevinhsieh","url":"https://community.spiceworks.com/u/kevinhsieh"}}]}}
HI
is there any benefit of having multiple targets created from a same disk pool?? i got 45 TB disk pool which i am planing to create one iscsi Target and assign it to 5 different host.
and will this effect if i want to create a sever cluster in the future ?? (Multipath i/O)
any advise please?
8 Spice ups
What kind of hosts do you plan to assign it to? You can only assign a LUN to multiple hosts if they are clustered, or if they are VMware ESXi. Most other cases will corrupt your data.
My rule of thumb is to leave enough free space on storage to fully clone whatever your largest object is. For a SAN, that means being able to fully clone the largest LUN. For a hypervisor with local storage, keep enough free space to be able to make a copy of the largest VMDK or VHDX somewhere. There are flexibility benefits of using smaller LUNs, and some performance benefits as well. I prefer to keep LUNs under 2 TB, even if I have 45 TB of available storage.
Note that SAN arrays also need free space for snapshots and normal operations. You should get alerts when your array gets close to full.
1 Spice up
donarachchi2:
HI
is there any benefit of having multiple targets created from a same disk pool?? i got 45 TB disk pool which i am planing to create one iscsi Target and assign it to 5 different host.
and will this effect if i want to create a sever cluster in the future ?? (Multipath i/O)
any advise please?
The answer is - it depends. Depends on what you use on a server side and on clients as well. Say MSFT target can’t scale well with multiple iSCSI sessions so increasing number of vLUNs having few iSCSI sessions / vLUN helps. Same about client - MSFT has issues with ~400K IOPS per LUN on client so having multiple vLUNs helps again. Linux / FreeBSD are different.
