Re: [pve-devel] [RFC cluster/manager/network 0/6] Add support for DHCP servers to SDN

["DERUMIER, Alexandre" <alexandre.derumier@groupe-cyllene.com>]

Le mardi 26 septembre 2023 à 16:12 +0200, Stefan Hanreich a écrit :
> > Yes, this is my main concern, as it'll be my case in production, as
> > I
> > managing multiple clusters, on differents location, with subnets
> > sharing.
> > 
> > for me, it's ok if ipam is down when allocating a new ip or vm.
> > But for vm start/stop, I think we should have at minimum some cache
> > somewhere. (I'm think about a disaster recovery or big network
> > problem,
> > where you want to fast restart all vms without need to call the
> > ipam).
> > 
> > Maybe a way, could be to use the local pve ipam, as a local mirror
> > of
> > the external ipam ?    (and don't store ip in vm config, but only
> > in
> > pve ipam, the source of truth)
> > 
> 
> Yes, I think this would be preferrable over the VM config. This also
> means we would have to sync from netbox to local PVE IPAMs?

See my pseudo algorithm, I think we can sync on the fly from netbox to
local pveipam (like a read cache), when we allocate a new ip.

I think it's not a problem with multiple cluster with different local
pveipam, if we always try to allocate a new ip from the external ip,
then write it to local pveipam, for later read.

Maybe it could be improve with a full sync of subnets in cron ? (Need
to check the external ipam apis)





> 
> > I'm a bit busy currently on other stuff and I would like to finish
> > them
> > first. 
> > 
> > So if you have a little bit time to work on this, it could be great
> > :)
> > 
> > I have send some patches in 2021 for ipam integration in qemu/lxc,
> > if
> > you want to take some inspiration. (without the ip in the vm
> > config, it
> > should be a lot easier)
> > 
> 
> I'll try to get on it then, I'll still be here for 2,5 weeks until I
> go
> on a longer vacation. Hopefully I'll get something workable ready
> until
> then. I will look into your patches - thanks for the hint!
> 
I'll have a little bit more time next week , then I'm going to do some
proxmox training with students, so I'll be busy until mid-october.
(so when you'll be in vacation ^_^).

If you have some early patches for this time, I'll be able to continue
the work if needed.



> > Yes,admin should be able to see allocated ip. (like a real ipam).
> > 
> > I was thinking about other stuff for later, but maybe it could be
> > great
> > for an admin to be able to reserve ips and put them in a pool.
> > Then user could choose ip from this pool.
> > 
> > (Usecase is public ip addresses, where a customer could buy some of
> > them,
> > then allocated them like he want)
> > 
> 
> That sounds like a great feature for hosters, I'll certainly look
> into that.
>