vMotion recommendation - help in understanding the Admin Guide vMotion statements
karad
12 Posts
November 21, 2023, 11:25 pmQuote from karad on November 21, 2023, 11:25 pmI've been turning this over in my head and I would like to validate if I'm following the recommendation on performance for the vMotion part mentioned in the Admin Guide.
My System:
14 Blades in a Chasis
2 NVMe per Blade
28 OSD in total
4 iface per blade (2 for BackEnd, 2 for ISCSI using vlan tagging)
3 Mgmt node + Storage
2 ISCSI + Storage nodes
9 Storage nodes
One rdb pool (3-2) that spread across all the storage nodes
I have created some ISCSI disks with only two active path
What I'm confused about is this part "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This means that should I have all the other nodes in Petasan serving as ISCSI as well.?
When I check the path assignment it spreads the paths between the two nodes assigned with the ISCSI role.
Am I following the best practice with this configuration?
Anything that could be improved based on what I mentioned?
Maybe an example will help clarify this further
Node 1 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.101 eth1.2081 00003 disk-infra1
y.x.81.102 eth1.2081 00004 disk-infra2
y.x.82.100 eth2.2082 00002 disk-images
Node 2 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.100 eth1.2081 00002 disk-images
y.x.82.101 eth2.2082 00003 disk-infra1
y.x.82.102 eth2.2082 00004 disk-infra2
Thank you
I've been turning this over in my head and I would like to validate if I'm following the recommendation on performance for the vMotion part mentioned in the Admin Guide.
My System:
14 Blades in a Chasis
2 NVMe per Blade
28 OSD in total
4 iface per blade (2 for BackEnd, 2 for ISCSI using vlan tagging)
3 Mgmt node + Storage
2 ISCSI + Storage nodes
9 Storage nodes
One rdb pool (3-2) that spread across all the storage nodes
I have created some ISCSI disks with only two active path
What I'm confused about is this part "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This means that should I have all the other nodes in Petasan serving as ISCSI as well.?
When I check the path assignment it spreads the paths between the two nodes assigned with the ISCSI role.
Am I following the best practice with this configuration?
Anything that could be improved based on what I mentioned?
Maybe an example will help clarify this further
Node 1 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.101 eth1.2081 00003 disk-infra1
y.x.81.102 eth1.2081 00004 disk-infra2
y.x.82.100 eth2.2082 00002 disk-images
Node 2 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.100 eth1.2081 00002 disk-images
y.x.82.101 eth2.2082 00003 disk-infra1
y.x.82.102 eth2.2082 00004 disk-infra2
Thank you
Last edited on November 21, 2023, 11:38 pm by karad · #1
admin
2,930 Posts
November 22, 2023, 12:45 amQuote from admin on November 22, 2023, 12:45 amYour path distribution across your iSCSI gateways are optimum for vmotion. You are only using 2 iSCSI nodes You do not need to do any changes.
If hypothetically you were using 10 iSCSI nodes, it is possible one of them will be serving a path for disk 1 but not for disk 2, if you were to perform storage vmotion across disk 1 -> disk 2, the vmotion hardware acceleration will not work and you will be using slow vmware controlled transfer. It such case you would use path assignment to "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
Note that version 3.2.0 had an issue with vmotion acceleration that was fixed in 3.2.1
Your path distribution across your iSCSI gateways are optimum for vmotion. You are only using 2 iSCSI nodes You do not need to do any changes.
If hypothetically you were using 10 iSCSI nodes, it is possible one of them will be serving a path for disk 1 but not for disk 2, if you were to perform storage vmotion across disk 1 -> disk 2, the vmotion hardware acceleration will not work and you will be using slow vmware controlled transfer. It such case you would use path assignment to "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
Note that version 3.2.0 had an issue with vmotion acceleration that was fixed in 3.2.1
Last edited on November 22, 2023, 12:46 am by admin · #2
karad
12 Posts
November 23, 2023, 8:30 amQuote from karad on November 23, 2023, 8:30 amok, I see, In the case that I decide to add two more ISCSI nodes, the recommendation will be to add more paths per ISCSI disk, in my case, have each disk with 4 paths.
That way each ISCSI node has the possibility to have a path for each disk, Am I right with this assumption?
thank you.
ok, I see, In the case that I decide to add two more ISCSI nodes, the recommendation will be to add more paths per ISCSI disk, in my case, have each disk with 4 paths.
That way each ISCSI node has the possibility to have a path for each disk, Am I right with this assumption?
thank you.
Last edited on November 23, 2023, 2:54 pm by karad · #3
admin
2,930 Posts
November 23, 2023, 8:13 pmQuote from admin on November 23, 2023, 8:13 pmThe main thing is
"...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This can be achieved by source and destination having 2 paths and having 2 iSCSI nodes serving one of the paths. Or 4 paths on 4 nodes..etc. This is the paragraph from the documentation:
"Before starting vmotion between 2 datastores/disks, make sure that all the paths of disk1 and disk2 are active on the same set of hosts, if they are not then you can move paths via the path assignment page. We want to avoid having a host that serves a path of 1 disk and not the other, this will slow down things significantly."
The main thing is
"...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This can be achieved by source and destination having 2 paths and having 2 iSCSI nodes serving one of the paths. Or 4 paths on 4 nodes..etc. This is the paragraph from the documentation:
"Before starting vmotion between 2 datastores/disks, make sure that all the paths of disk1 and disk2 are active on the same set of hosts, if they are not then you can move paths via the path assignment page. We want to avoid having a host that serves a path of 1 disk and not the other, this will slow down things significantly."
vMotion recommendation - help in understanding the Admin Guide vMotion statements
karad
12 Posts
Quote from karad on November 21, 2023, 11:25 pmI've been turning this over in my head and I would like to validate if I'm following the recommendation on performance for the vMotion part mentioned in the Admin Guide.
My System:
14 Blades in a Chasis
2 NVMe per Blade
28 OSD in total
4 iface per blade (2 for BackEnd, 2 for ISCSI using vlan tagging)3 Mgmt node + Storage
2 ISCSI + Storage nodes
9 Storage nodesOne rdb pool (3-2) that spread across all the storage nodes
I have created some ISCSI disks with only two active pathWhat I'm confused about is this part "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This means that should I have all the other nodes in Petasan serving as ISCSI as well.?When I check the path assignment it spreads the paths between the two nodes assigned with the ISCSI role.
Am I following the best practice with this configuration?
Anything that could be improved based on what I mentioned?Maybe an example will help clarify this further
Node 1 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.101 eth1.2081 00003 disk-infra1
y.x.81.102 eth1.2081 00004 disk-infra2
y.x.82.100 eth2.2082 00002 disk-images
Node 2 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.100 eth1.2081 00002 disk-images
y.x.82.101 eth2.2082 00003 disk-infra1
y.x.82.102 eth2.2082 00004 disk-infra2Thank you
I've been turning this over in my head and I would like to validate if I'm following the recommendation on performance for the vMotion part mentioned in the Admin Guide.
My System:
14 Blades in a Chasis
2 NVMe per Blade
28 OSD in total
4 iface per blade (2 for BackEnd, 2 for ISCSI using vlan tagging)
3 Mgmt node + Storage
2 ISCSI + Storage nodes
9 Storage nodes
One rdb pool (3-2) that spread across all the storage nodes
I have created some ISCSI disks with only two active path
What I'm confused about is this part "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This means that should I have all the other nodes in Petasan serving as ISCSI as well.?
When I check the path assignment it spreads the paths between the two nodes assigned with the ISCSI role.
Am I following the best practice with this configuration?
Anything that could be improved based on what I mentioned?
Maybe an example will help clarify this further
Node 1 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.101 eth1.2081 00003 disk-infra1
y.x.81.102 eth1.2081 00004 disk-infra2
y.x.82.100 eth2.2082 00002 disk-images
Node 2 - 3 Paths
IP Address Interface Disk ID Disk Name
y.x.81.100 eth1.2081 00002 disk-images
y.x.82.101 eth2.2082 00003 disk-infra1
y.x.82.102 eth2.2082 00004 disk-infra2
Thank you
admin
2,930 Posts
Quote from admin on November 22, 2023, 12:45 amYour path distribution across your iSCSI gateways are optimum for vmotion. You are only using 2 iSCSI nodes You do not need to do any changes.
If hypothetically you were using 10 iSCSI nodes, it is possible one of them will be serving a path for disk 1 but not for disk 2, if you were to perform storage vmotion across disk 1 -> disk 2, the vmotion hardware acceleration will not work and you will be using slow vmware controlled transfer. It such case you would use path assignment to "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
Note that version 3.2.0 had an issue with vmotion acceleration that was fixed in 3.2.1
Your path distribution across your iSCSI gateways are optimum for vmotion. You are only using 2 iSCSI nodes You do not need to do any changes.
If hypothetically you were using 10 iSCSI nodes, it is possible one of them will be serving a path for disk 1 but not for disk 2, if you were to perform storage vmotion across disk 1 -> disk 2, the vmotion hardware acceleration will not work and you will be using slow vmware controlled transfer. It such case you would use path assignment to "...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
Note that version 3.2.0 had an issue with vmotion acceleration that was fixed in 3.2.1
karad
12 Posts
Quote from karad on November 23, 2023, 8:30 amok, I see, In the case that I decide to add two more ISCSI nodes, the recommendation will be to add more paths per ISCSI disk, in my case, have each disk with 4 paths.
That way each ISCSI node has the possibility to have a path for each disk, Am I right with this assumption?
thank you.
ok, I see, In the case that I decide to add two more ISCSI nodes, the recommendation will be to add more paths per ISCSI disk, in my case, have each disk with 4 paths.
That way each ISCSI node has the possibility to have a path for each disk, Am I right with this assumption?
thank you.
admin
2,930 Posts
Quote from admin on November 23, 2023, 8:13 pmThe main thing is
"...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This can be achieved by source and destination having 2 paths and having 2 iSCSI nodes serving one of the paths. Or 4 paths on 4 nodes..etc. This is the paragraph from the documentation:
"Before starting vmotion between 2 datastores/disks, make sure that all the paths of disk1 and disk2 are active on the same set of hosts, if they are not then you can move paths via the path assignment page. We want to avoid having a host that serves a path of 1 disk and not the other, this will slow down things significantly."
The main thing is
"...make sure that all the paths of disk1 and disk2 are active on the same set of hosts..."
This can be achieved by source and destination having 2 paths and having 2 iSCSI nodes serving one of the paths. Or 4 paths on 4 nodes..etc. This is the paragraph from the documentation:
"Before starting vmotion between 2 datastores/disks, make sure that all the paths of disk1 and disk2 are active on the same set of hosts, if they are not then you can move paths via the path assignment page. We want to avoid having a host that serves a path of 1 disk and not the other, this will slow down things significantly."