Prevent bonding issue by removing extra network interface from bridge_ports on sle12 autoyast

[Julie-CAO]

The incorrect network bridge configuration is causing problem:

The machine bare-metal2.oqa.prg2.suse.org act as router and created illegal duplicate traffics for gateway of the oqa.prg2.suse.org subnet.
We sow "DUP" responses for ping toward vlan gateway 10.145.10.254 not just in k2 VM but also in other machines like for example on DHCP servers.

We investigated the traffics and found evidences about problematic traffics in J11 TOR switches specifically on port 5 on both TORs. ports are used by the server bare-metal2.oqa.prg2.suse.org as eth0 and eth1 see: https://racktables.nue.suse.com/index.php?page=object&object_id=23403
Our suspicion is incorrect setup bond between eth0 and eth1 interfaces that want to be LACP bond, but that is not setup on our side and in he end act as loop in this vlan.

bare-metal2:/etc/sysconfig/network # cat ifcfg-br0
BOOTPROTO='dhcp'
BRIDGE='yes'
BRIDGE_FORWARDDELAY='15'
BRIDGE_PORTS='eth0 eth1 em1 em2'
BRIDGE_STP='off'
STARTMODE='auto'

The culprit is BRIDGE_PORTS='eth0 eth1 em1 em2'. "make a bridge from two interfaces is bad practice"

• Verification run:
  sle12sp5_kvm_on_gonzo
  sle12sp5_kvm_on_fozzie
  sle12sp5_kvm_on_amd-zen3
  sle12sp5_kvm_on_blackbauhinia
  sle12sp5_xen_on_fibnacci

[Julie-CAO]

The verification runs with the new introduced setting BRIDGE_PORT:
sle12sp5_kvm_on_unreal3
sle12sp5_kvm_on_gonzo
sle12sp5_kvm_on_amd-zen3
sle12sp5_kvm_on_blackbauhinia
sle12sp5_kvm_on_ph052

And please merge this PR after https://gitlab.suse.de/openqa/salt-pillars-openqa/-/merge_requests/867 is merged.

[Julie-CAO]

FYI. The MU sle12 autoyast template has the similar problem. It will not bring troubles if there will always be one cable connection to the master Ethernet card on machines, but I'd like to raise this problem here to bring your awareness. @alice-suse @waynechen55 @RoyCai7 @tbaev @martinsmarcelo

  <networking>
    <keep_install_network config:type="boolean">true</keep_install_network>
    <managed config:type="boolean">false</managed>
    <interfaces config:type="list">
      <interface>
        <device>br0</device>
        <bootproto>dhcp</bootproto>
        <bridge>yes</bridge>
        <bridge_forwarddelay>0</bridge_forwarddelay>
        <bridge_ports>eth0 eth1</bridge_ports>
        <bridge_stp>off</bridge_stp>
        <startmode>auto</startmode>
      </interface>
    </interfaces>
  </networking>

[alice-suse]

lgtm, thanks for the quick fix