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changing vlans

Hello,

Have a need to change the management vlan (not IP's) to something else and wanted to see if the following procedure will crash it.  I know one node of 3 can be shut down but when two does, it might not work with the replication.  We have 3 nodes.

Since this is the storage for a VMware cluster, we'll stop all VM's so data is not sent to the PetaSan.

  1.  Change the file to reflect the new vlan on each node
  2.   Shut down all nodes at the same time
  3.   Power on each node one at a time.

Not sure about powering each node on in sequence or all at once.  What's your advice?

 

question, since we are just changing the management VLAN, can I change the vlan in /interfaces and just restart the service?  If we can do this for 3 node quickly, will things sync up?

You need to change /etc/network/interfaces to reflect the new vlan id, this file is used at boot time.

You probably do not need a reboot, you should be able to change this without affecting io.  i would recommend you ssh to each node using backend 1 ip then as example to change id from 9 to 10

ip link del eth0.9
ip link add link eth0 name eth0.10 type vlan id 10
ip link set dev eth0.10 up
ip address add 10.0.1.11/255.255.255.0 dev eth0.10

if using bonding, replace eth0 for example to bond0 or whatever.

If not using bonding you may be able to use ifup and ifdown but i recommend the above steps.

If you will reboot, then changes to  /etc/network/interfaces  should be all that is needed.  Booting all nodes together is better as if you wait a couple of minutes they will start in a degraded state and it some cases may start recovery.

Do not forget to change settings on your swicthes

Went with the changing of the interface file then reboot.  Made sure all my vm clients where off or moved locally, than rebooted.  Everything went very well.  Restarted the Iscsi disk and it worked, only had a clock skew a little off and that just needed time.  Thanks for your advice.  You have an excellent product and your responses are top notch.