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flatdhcpmanager out of static ips

asked 2015-12-15 14:47:02 -0500

ramonskie gravatar image

updated 2015-12-15 14:47:58 -0500

i use nova-network with flatdhcpmanager and now i'm out of static ips. ( icehouse runs for more than 3 years ) and have more than 200 vms running.. anybody know the best course of action here?

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answered 2015-12-15 23:38:51 -0500

Prateek K gravatar image

That's a tricky one.... well the solution is not simple but not impossible either... As you said you are on icehouse then it means that we can migrate from nova-network to neutron or nova-network also supports VLAN. Having said that I am assuming that we can restart the VM's that are present on the environment(Only If Required).

So here is what I can suggest you :-

  1. Create snapshots and backup of configuration so that in case something bad happens we can restore everything back to its original state( I suggest if you have some dummy machines also test the backup that you have created)

  2. Enable VLAN networking in nova-network

  3. Create a VLAN network. Follow this in case of any issues -

  4. Create VM's in this VLAN network and see if it works.(IP from dhcp, pinging, basic stuff)

  5. Create a virtual router

  6. Take an IP from the DHCP network and IP from VLAN network and add them as router interfaces.

  7. Ping VM1 to VM2 where VM1 is in dhcpflat network and VM2 is in the newly created VLAN network(should work)

Once you have done that though you will be technically having 2 network's i.e. one pre exsisting dhcp network and one VLAN network but still you will be able to ping machines as the networks are connected via the router. Another thing is now your networking has become scalable and you can create as number of networks as you want .

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how can i enable vlan networking and flatdhcp? or do i need to create a extra node with nova-network with a different configuration?

or can we just test it with 1 or 2 compute nodes first or do we need to update all nova.conf files on all compute nodes because we use multi-host=true

ramonskie gravatar imageramonskie ( 2015-12-16 03:43:59 -0500 )edit

follow that guide to enable vlan networking along with dhcp... Dont change your dhcp configuration it should not affect vlan networking.... Just test it with 1 compute node then we can see

Prateek K gravatar imagePrateek K ( 2015-12-16 04:51:27 -0500 )edit

when i put anew compute node with the following config it meseed up the database network record that was used by flatdhcp so i overlooked something any ideas?

ramonskie gravatar imageramonskie ( 2015-12-17 11:11:26 -0500 )edit

answered 2015-12-17 11:21:14 -0500

ramonskie gravatar image

is there a possibility to change move the flatdhcp to a larger vlan i thought maby i can add a larger ip range and then alter the records in the database is that a option?

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Asked: 2015-12-15 14:47:02 -0500

Seen: 88 times

Last updated: Dec 17 '15