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Connectivity between instances running in diferents computes nodes

asked 2016-06-22 04:39:03 -0600

Daniel Ruiz gravatar image


I'm mananing a Juno Openstack cloud... Yes, I know: I should upgrade to Mitaka, but because of all computes act as students computers, I can't "touch" anything... So, by the moment, Juno will be my version...

My scenario is: One server that acts as controller and network node, with 3 nics: one for management, one for VM-data and one for "external" (with no IP address configured). In my Lab, all machines have public IP, so management nic has configured a public IP 20 computes that act as computes nodes, with 2 nics: one for management (and, like in controller, with one public IP) and one for VM-data

Configuration files (in server and computes) are, always, using public IPs (eth1) and only in ml2_conf.ini (in neutron plugins) I have configured "local_ip=private_IP_value" for openvswitch

With this configuration, when I launch "n" instances and they are running in more than one computer, there are no connectivity between instances running in different computes. However, in instances running in the same compute I can ping each other... All instances get a valid IP from my configured private network (I can see them at dashboard), but I run a VNC console, I can check the problem with connectivity

What can I do? How can I debug this problem?

Thanks, thanks a lot!!! I need this help :( :( :(

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When you ping VM running on different Compute node which IP ( private or public ) do you use ?

dbaxps gravatar imagedbaxps ( 2016-06-22 06:27:54 -0600 )edit

I try to ping a VM running on different compute from inside a VM, not from a compute, so I try to ping to an private address leases from dhcp agent running in my private network (created from dashboard or CLI).

Daniel Ruiz gravatar imageDaniel Ruiz ( 2016-06-22 06:49:08 -0600 )edit

From within VM1 try ping public IP of VM2
If it would work upload ssh keypair VM1 and try connect to VM2 via ssh.

dbaxps gravatar imagedbaxps ( 2016-06-22 07:52:38 -0600 )edit

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answered 2016-06-29 08:24:24 -0600

jckreddy gravatar image

updated 2016-06-29 08:49:38 -0600

One solution for this problem is assigning floating(public-ip) to VMs

Compute1--> VM1--->VM IP1 ---> Floating-ip1
Compute1--> VM2--->VM IP2 ---> Floating-ip2

now you can ping floating-ip1/2 from vm1/vm2
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answered 2016-06-27 06:28:18 -0600

Daniel Ruiz gravatar image

updated 2016-06-27 06:28:43 -0600

I have reconfigured all scenario and I have reinstalled ALL with Mitaka version. Problem persists... so it's not caused by a bug. It's a configuration problem... How can I configure with Mitaka and 2 nics: first nic has ALWAYS public IP and, also, is for management in openstack and second nic is for VM data (creating, deleting, etc).


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Asked: 2016-06-22 04:39:03 -0600

Seen: 136 times

Last updated: Jun 29 '16