Bug 1751079

Summary: Keep MTU settings of interface if possible after base interface MTU changes
Product: Red Hat Enterprise Linux 8 Reporter: Ales Musil <amusil>
Component: NetworkManagerAssignee: Beniamino Galvani <bgalvani>
Status: CLOSED ERRATA QA Contact: Desktop QE <desktop-qa-list>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 8.2CC: atragler, bgalvani, edwardh, fgiudici, lrintel, mburman, pasik, ptalbert, rkhan, sukulkar, thaller, toneata, vbenes
Target Milestone: rcKeywords: ZStream
Target Release: 8.2Flags: pm-rhel: mirror+
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: NetworkManager-1.22.0-0.1.el8 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of:
: 1770691 1779162 (view as bug list) Environment:
Last Closed: 2020-04-28 16:53:06 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1751695, 1770691, 1779162    
Attachments:
Description Flags
Reproducer none

Description Ales Musil 2019-09-11 07:02:09 UTC
Created attachment 1613928 [details]
Reproducer

Description of problem:

Considering scenario eth0 and two VLANs on top eth0.10 and eth.20 all of them with MTU 2000. When we change the MTU of eth0 and eth0.20 and apply this config the MTU of eth0.10 is reverted to default value (1500), but in the NM has still 2000 in the config. 


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

NetworkManager-1.20.0-3.el8.x86_64

How reproducible:

100%

Steps to Reproduce:

Full reproducer is in attachment. 

Actual results:

76: dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 2200 
77: dummy_abc.10@dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 
79: dummy_abc.20@dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 2200 


Expected results:

76: dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 2200 
77: dummy_abc.10@dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 2000 
79: dummy_abc.20@dummy_abc: <BROADCAST,NOARP,UP,LOWER_UP> mtu 2200

Comment 2 Edward Haas 2019-09-20 09:22:16 UTC
Can you please target this for RHEL 8.1.1?

Comment 5 Edward Haas 2019-10-29 09:25:33 UTC
(In reply to Beniamino Galvani from comment #4)
> (In reply to Beniamino Galvani from comment #3)
> 

Editing the MTU/s on a server, especially on a hypervisor is a common practice and supported by layered products like RHV.
This problem seems like a regression (seems to have worked before) and it is too basic not to handle as soon as possible.

Comment 7 sushil kulkarni 2019-10-29 14:27:12 UTC
Setting flags for inclusion in 8.1.z.

Anita, can you please approve this Z stream request by setting zstream+ ?

Thanks!
Sushil

Comment 11 errata-xmlrpc 2020-04-28 16:53:06 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, 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-2020:1847