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big-judge-33880

02/13/2023, 11:30 AM
Is there any guidance on pitfalls related to reconfiguring the networks in an existing harvester cluster? Currently all machines on vlan networks are connected to the management cluster network (due to initial hardware constraints), but with more network interfaces I’d like to fan out and use separate VM and storage networks
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great-bear-19718

02/13/2023, 10:08 PM
could you please elaborate? are you planning to add more VM networks and migrate workload VM's to use the new VM networks?
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big-judge-33880

02/14/2023, 8:24 AM
I’m currently running the management network with no vlan set, and would like to apply a vlan id to it. Ideally I’d want to move this to a new network, too, but I assume that might be more difficult in practice. Then I’d like to move all the VMs currently using the management network over to a new cluster network for VMs, while adding a separate storage network for longhorn to use.
(aka break things, probably)
I’d also want to change the physical interfaces used for the management bond, so I’m thinking of something like this admittedly naive plan: 1. Making changes in /oem configuration for management bond to use 1Gbit interfaces (currently running on a bond of 10Gbit interfaces) - same IP addresses as before, but now vlan-tagged 2. Shut down and restart all nodes 3. Create two cluster network for vms and storage (VM network to reuse interfaces previously used by management) 4. Shut down all VMs 5. Attach all VMs to new networks connected to new vm cluster network 6. Set up storage network according to docs 7. Start all VMs and cross fingers
g

great-bear-19718

02/14/2023, 10:31 PM
changes to /oem/harvester.config will not be applied to the underlying interfaces. that is more of a place holder and is used to generated /oem/99_ custom.yaml which has the OS configuration instructions
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big-judge-33880

02/14/2023, 10:50 PM
Yeah, thank you. I assumed that since harvester.conf contains the initial setup of the cluster from an older version. Am I correct in assuming I can simply replace the interface names associated with the management network in 99_custom.yaml if I ensure the the same vlan and aggregation settings are available on the switch connected to the new interfaces? As far as I can tell /etc/sysconfig/network/ gets overwritten on boot, so no need to clean out the old interface configs?
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great-bear-19718

02/14/2023, 10:51 PM
yeah 99_custom.yaml is what is applied, in there they will be a setup script for the interfaces which applies the vlan id when creating the br and bo interfaces
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big-judge-33880

02/14/2023, 11:02 PM
Thanks a lot for your input!