Bug 1805645

Summary: [Docs] Clarify that Compute nodes require external bridge for DVR
Product: Red Hat OpenStack Reporter: Stephane Vigan <svigan>
Component: documentationAssignee: Greg Rakauskas <gregraka>
Status: CLOSED CURRENTRELEASE QA Contact: RHOS Documentation Team <rhos-docs>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 16.0 (Train)CC: amoralej, dsneddon, gfidente, gregraka, jamsmith, kchamart, rhandlin
Target Milestone: asyncKeywords: Documentation, Triaged
Target Release: 16.1 (Train on RHEL 8.2)   
Hardware: Unspecified   
OS: Unspecified   
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Last Closed: 2022-05-13 19:30:28 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Stephane Vigan 2020-02-21 09:41:32 UTC
Description of problem:

Since OVN is default in OSP16 and DVR is enable by default, architecture reference need to explicitly specify we need an external network on all kind of compute node.

Version-Release number of selected component (if applicable):

OSP16

Comment 2 Dan Sneddon 2020-10-02 22:43:35 UTC
(In reply to Stephane Vigan from comment #0)
> Description of problem:
> 
> Since OVN is default in OSP16 and DVR is enable by default, architecture
> reference need to explicitly specify we need an external network on all kind
> of compute node.
> 
> Version-Release number of selected component (if applicable):
> 
> OSP16

To be clear, the compute nodes require an external bridge to be able to attach a VLAN or flat network for external router gateway and hosting floating IPs on the Compute nodes and performing SNAT for VMs with floating IPs.

The Compute nodes do not require (and should not have in most cases) a connection to the External network or an IP directly on that network. The External network is used on the Compute nodes for hosting the External VIP and public API endpoints as well as Horizon. The external bridge is used by Neutron for attaching external network(s) for NAT and floating IPs. When DVR is enabled (which is the default with OVN in OSP 16) the Compute nodes will need an external bridge that matches the Controller nodes, and matching bridge mappings.