Network Team with VLANs on pruned trunk "getting IP", fails [solved]

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Aqualinx
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Joined: 2017/04/03 17:31:15

Network Team with VLANs on pruned trunk "getting IP", fails [solved]

Post by Aqualinx » 2020/01/16 16:37:19

Hello!

I am setting up VLANs on a Network Team using the LACP (802.3ad) runner and two local NICs. The switch ports are configured as pruned trunks with untagged (native) VLAN disabled. Therefore, I would expect the VLAN interfaces to pull DHCP IPs, which they do as confirmed by:
nmcli c show CNAME
I would also expect non-VLAN interfaces, such as the master team interface, to not be able to pull DHCP IPs or pass traffic, as intended. The issue I am having is that the master team interface attempts to obtain an IP and then fails. When it fails the team goes down and the VLAN interfaces with it.

I have tried setting
BOOTPROTO=none
in the ifcfg file then
nmcli c reload
, with no change.

This behavior seems similar to https://bugzilla.redhat.com/show_bug.cg ... id=1183424

I am doing this on CentOS Linux release 7.7.1908 (Core).

I would be happy to post any additional details or config files if it helps. I have just tried to keep this initial post short.

Thank you so very much for your assistance,
Charles

[edit - add CentOS version]
Last edited by Aqualinx on 2020/01/16 21:09:34, edited 1 time in total.

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jlehtone
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Location: Finland

Re: Network Team with VLANs on pruned trunk "getting IP", fails

Post by jlehtone » 2020/01/16 18:18:38

The bug you link to (and its duplicate) were for NetworkManager-based configuration and NM got a patch back then.

I do use NM and don't even look at those files. I have set up a system with LACP-Team and VLANs.

What do you get after:

Code: Select all

nmcli con mod CNAME ipv4.method disabled ipv6.method ignore
where CNAME is name of the team.

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Aqualinx
Posts: 5
Joined: 2017/04/03 17:31:15

Re: Network Team with VLANs on pruned trunk "getting IP", fails

Post by Aqualinx » 2020/01/16 19:22:15

Hi jlehtone,

Thank you very much for the reply.

After executing your suggested command:

Code: Select all

nmcli con mod CNAME ipv4.method disabled ipv6.method ignore
the team and VLAN are stable. I can see the MLAG bond on my switch pair and both "nmcli c show" and "nmcli d status" show green. Unfortunately, when I look at:

Code: Select all

ip addr
the VLAN interfaces show subnet address (e.g. "inet 192.168.1.0/24 brd 192.168.1.255") not network IP. I deleted interfaces just now, adjusted my switches from trunks to access ports on one VLAN, and rebuilt the team without VLAN and pull an IP just fine (can SSH in, etc.), so it is not a firewall, route or DHCP issue I don't think.

Immediately after your suggestion (it used to look like this then drop):
2020-01-16_13-39-01.jpg
2020-01-16_13-39-01.jpg (157.88 KiB) Viewed 220 times
After your suggestion, it didn't drop:
2020-01-16_14-05-52.jpg
2020-01-16_14-05-52.jpg (145.69 KiB) Viewed 220 times
ip addr:
2020-01-16_14-18-24.jpg
2020-01-16_14-18-24.jpg (151.4 KiB) Viewed 220 times
These are test subnets on lab hardware.

Any further suggestions on how I might troubleshoot this would be most appreciated!

Respectfully,
Charles

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Aqualinx
Posts: 5
Joined: 2017/04/03 17:31:15

Re: Network Team with VLANs on pruned trunk "getting IP", fails

Post by Aqualinx » 2020/01/16 21:08:36

I have answered my own follow-up question. I misunderstood some documentation examples and had misconfigured my VLAN slaves.

jlehtone's answer solved my issue, thank you!

Thank you very much for your time and consideration,
Charles

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