Bug 1905233 - Incorrect interface selection when creating keepalived configuration for IPv6
Summary: Incorrect interface selection when creating keepalived configuration for IPv6
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: OpenShift Container Platform
Classification: Red Hat
Component: Networking
Version: 4.6
Hardware: Unspecified
OS: Unspecified
urgent
high
Target Milestone: ---
: 4.7.0
Assignee: Yossi Boaron
QA Contact: Rei
URL:
Whiteboard: OCP-Metal-External-Blocker
Depends On: 1925291 1927068
Blocks:
TreeView+ depends on / blocked
 
Reported: 2020-12-07 19:27 UTC by Ori Amizur
Modified: 2021-03-10 11:24 UTC (History)
6 users (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Cause: Set overlapping IPV6 subnets for different NICs, for example: Interface A subnet: 1001:db8::/120 , Interface B subnet: 1001:db8::f00/120 VIP address 1001:db8::64 Consequence: The wrong interface was set in Keepalived conf file and as a result, the deployment failed. Fix: Select the NIC whose address is L2 connected with the VIP address. Result: The correct interface is selected for Keepalived conf
Clone Of:
Environment:
Last Closed: 2021-03-10 11:24:01 UTC
Target Upstream Version:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Github openshift baremetal-runtimecfg pull 112 0 None closed Bug 1905233: get the correct VRRP interface in case of IPV6 overlapping subnets 2021-02-19 16:56:11 UTC
Red Hat Product Errata RHBA-2021:0678 0 None None None 2021-03-10 11:24:36 UTC

Description Ori Amizur 2020-12-07 19:27:59 UTC 
Description of problem:

When trying to install a cluster with two interfaces a wrong interface is selected for the VIPs.  The 2 subnets are 1001:db8::/120, and 1001:db8::f00/120.
The VIPs are API 1001:db8::64, Ingress 1001:db8::65.  When wrong interface is selected, the installation is stuck.

How reproducible:

Try install a cluster with these two subnets. It happened with Assisted Installer.


Actual results:

The interface of the second subnet is selected.  Therefore, the VIPs are configured on this interface on every master node.


Expected results:

The selected interface should be on the first subnet.


Additional info:

The problem is probably here.  

https://github.com/openshift/baremetal-runtimecfg/blob/a9f2b4411e93d10e5459f6b07cc490c39da7c8b2/pkg/config/net.go#L36-#L39

Instead of replacing the prefix, the prefix should be calculated from the RA routes.
Comment 7 errata-xmlrpc 2021-03-10 11:24:01 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (OpenShift Container Platform 4.7.1 bug fix update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2021:0678
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