... | ... | @@ -1327,7 +1327,17 @@ This will only migrate the VMs without rebooting the hosts: |
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./reboot --ganeti-migrate-back --kind=cancel -v --reason 'qemu flagged in needrestart' \
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-H fsn-node-0{1,2,3,4,5,6,7,8}.torproject.org
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This should cause no user-visible disruption.
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This should cause no user-visible disruption, as it migrates all the
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VMs around and back.
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That should reset the Qemu processes across the cluster and refresh
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the libraries Qemu depends on.
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If you actually need to restart the instances in place (and not
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migrate them), you need to use the `--skip-ganeti-empty` flag instead:
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./reboot --skip-ganeti-empty --kind=cancel -v --reason 'qemu flagged in needrestart' \
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-H dal-node-0{1,2,3}.torproject.org
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## Rebalancing a cluster
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... | ... | @@ -3123,6 +3133,7 @@ gnt-cluster modify -H kvm:disk_type=scsi-hd |
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gnt-cluster modify -H kvm:migration_bandwidth=950
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gnt-cluster modify -H kvm:migration_downtime=500
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gnt-cluster modify -H kvm:migration_caps=postcopy-ram
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gnt-cluster modify -H kvm:cpu_type=host
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gnt-cluster modify -D drbd:c-plan-ahead=0,disk-custom='--c-plan-ahead 0'
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gnt-cluster modify --uid-pool 4000-4019
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```
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... | ... | @@ -3298,7 +3309,7 @@ emulation system to the CPU on the node. But that might make the live |
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migration more brittle: VMs or processes can crash after a live
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migrate because of a slightly different configuration (microcode, CPU,
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kernel and QEMU versions all play a role). So we need to find the
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lowest common demoninator in CPU families. The list of available
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lowest common denominator in CPU families. The list of available
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families supported by QEMU varies between releases, but is visible
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with:
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... | ... | @@ -3337,6 +3348,8 @@ to be verified. |
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Nodes could also [grouped](http://docs.ganeti.org/docs/ganeti/3.0/html/man-gnt-group.html) to limit (automated) live migration to a
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subset of nodes.
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Update: this was enabled in the `gnt-dal` cluster.
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References:
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* <https://dsa.debian.org/howto/install-ganeti/>
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... | ... | |