[ovirt-users] Migrating self-HostedEngine from NFS to iSCSI
Hello,
I have a few questions regarding migration of HostedEngine. Currently I
have a cluster of 3 oVirt 4.3.3 nodes, all three of them are capable of
running HE and I can freely migrate HostedEngine and regular VMs between
them. However I deployed HostedEngine storage on rather edgy NFS server
and I would like to migrate it to iSCSI based storage with multipathing.
Quite a few VMs are already running on cluster and are using iSCSI data
storage.
Documentation is rather chaotic and fragmented, but from what I gathered
the path of migration is someting like:
- place one host (#1), the "failover" host, into maintenance mode prior
to backup
- export configuration with engine-backup
- set global maintenance mode on all hosts
- install ovirt engine on that host (#1) (already installed, since this
is HE capable host)
- restore engine configuration using engine-backup
- run engine-setup with new parameters regarding storage
- after engine-setup, log into admin portal and remove old host (#1)
- redeploy hosts #2 and #3
Last two steps are a bit confusing as I'm not sure how removing old
failover host on which new HE is running would work. Also not
understanding the part where hosts 2 and 3 are described as
unrecoverable (but with running VMs, which I'd have to live migrate to
other hosts - how, if they're not operational?).
Few other things:
- Should I first remove & re-add host #1 without HE already deployed on
host?
- Should I set global maintenance mode on all hosts before migration?
I'm guessing this is required if I want to prevent HE being started on
random host during transition...
- Which host should be selected as SPM during the transition phase?
- How can I configure iSCSI multipathing? Self-hosted engine
documentation mentions Multipath Helper tool, however I cannot find any
info about it. Is this tool freely available or only a part od RHEL
subscription?
- Can I configure existing iSCSI Domain which already hosts some VMs as
HE storage? Or do I have to assign extra LUN/target exclusively for HE?
Cheers
--
Miha