[CentOS] nmcli: unwanted secondary ip-address

Thu Sep 24 07:42:34 UTC 2020
Felix Kölzow <felix.koelzow at gmx.de>

Dear Mark,

thanks for the additional hints.

On 22/09/2020 17:26, Mark Milhollan wrote:
> On Tue, 22 Sep 2020, Felix Kölzow wrote:
>
>> A secondary ip address seems to be automatically added to a nic which
>> causes several issues in our setup.
>
>> # nmcli con show
>> NAME      UUID                                  TYPE      DEVICE
>> eno4      dbd95c24-1ed7-4292-8dba-3934bd1476a0  ethernet  eno4
>
>> 6: eno4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP 
>> group default qlen 1000
>>     link/ether 00:26:b9:78:87:d7 brd ff:ff:ff:ff:ff:ff
>>     inet 192.168.2.98/24 brd 192.168.2.255 scope global noprefixroute 
>> eno4
>>        valid_lft forever preferred_lft forever
>>     inet *192.168.137.223/24* brd 192.168.137.255 scope global 
>> dynamic eno4      <<----- THIS IS UNWANTED
>>        valid_lft 604778sec preferred_lft 604778sec
>>     inet6 fe80::9257:5654:b211:8dea/64 scope link noprefixroute
>>        valid_lft forever preferred_lft forever
>
> You failed to show the configuration of eno4's profile in Network 
> Manager (nmcli con show eno4).  You can use 'nmcli con edit' (or 
> nmtui) to modify the profile to eliminate the assignment of the 
> unwanted address -- if it is in automatic mode (which seems to be the 
> case) then you may need to fix your DHCP server instead.  If there is 
> no chance that Network Manager is assigning the extra address then you 
> will have to hunt around your system for the program or script that is 
> doing so.
>
>
> /mark

>
> You failed to show the configuration of eno4's profile in Network 
> Manager (nmcli con show eno4).
Yes, indeed, it was missing. The method is set to manual (additional 
marked), see below.

# nmcli con edit eno4

===| nmcli interactive connection editor |===

nmcli> p
===============================================================================
                        Connection profile details (eno4)
===============================================================================
connection.id:                          eno4
connection.uuid: dbd95c24-1ed7-4292-8dba-3934bd1476a0
connection.stable-id:                   --
connection.type:                        802-3-ethernet
connection.interface-name:              eno4
connection.autoconnect:                 yes
connection.autoconnect-priority:        0
connection.autoconnect-retries:         -1 (default)
connection.multi-connect:               0 (default)
connection.auth-retries:                -1
connection.timestamp:                   1600932622
connection.read-only:                   no
connection.permissions:                 --
connection.zone:                        --
connection.master:                      --
connection.slave-type:                  --
connection.autoconnect-slaves:          -1 (default)
connection.secondaries:                 --
connection.gateway-ping-timeout:        0
connection.metered:                     unknown
connection.lldp:                        default
connection.mdns:                        -1 (default)
connection.llmnr:                       -1 (default)
connection.wait-device-timeout:         -1
-------------------------------------------------------------------------------
802-3-ethernet.port:                    --
802-3-ethernet.speed:                   0
802-3-ethernet.duplex:                  --
802-3-ethernet.auto-negotiate:          no
802-3-ethernet.mac-address:             --
802-3-ethernet.cloned-mac-address:      --
802-3-ethernet.generate-mac-address-mask:--
802-3-ethernet.mac-address-blacklist:   --
802-3-ethernet.mtu:                     auto
802-3-ethernet.s390-subchannels:        --
802-3-ethernet.s390-nettype:            --
802-3-ethernet.s390-options:            --
802-3-ethernet.wake-on-lan:             default
802-3-ethernet.wake-on-lan-password:    --
-------------------------------------------------------------------------------
ipv4.method:                            manual######## 
<<<--------------- IS SET TO MANUAL
ipv4.dns: 10.10.100.1,10.10.100.2
ipv4.dns-search:                        --
ipv4.dns-options:                       --
ipv4.dns-priority:                      0
ipv4.addresses:                         192.168.2.98/24
ipv4.gateway:                           --
ipv4.routes:                            --
ipv4.route-metric:                      -1
ipv4.route-table:                       0 (unspec)
ipv4.routing-rules:                     --
ipv4.ignore-auto-routes:                yes
ipv4.ignore-auto-dns:                   yes
ipv4.dhcp-client-id:                    --
ipv4.dhcp-iaid:                         --
ipv4.dhcp-timeout:                      0 (default)
ipv4.dhcp-send-hostname:                yes
ipv4.dhcp-hostname:                     --
ipv4.dhcp-fqdn:                         --
ipv4.dhcp-hostname-flags:               0x0 (none)
ipv4.never-default:                     yes
ipv4.may-fail:                          yes
ipv4.dad-timeout:                       -1 (default)
-------------------------------------------------------------------------------
ipv6.method:                            auto
ipv6.dns:                               --
ipv6.dns-search:                        --
ipv6.dns-options:                       --
ipv6.dns-priority:                      0
ipv6.addresses:                         --
ipv6.gateway:                           --
ipv6.routes:                            --
ipv6.route-metric:                      -1
ipv6.route-table:                       0 (unspec)
ipv6.routing-rules:                     --
ipv6.ignore-auto-routes:                no
ipv6.ignore-auto-dns:                   no
ipv6.never-default:                     yes
ipv6.may-fail:                          yes
ipv6.ip6-privacy:                       -1 (unknown)
ipv6.addr-gen-mode:                     stable-privacy
ipv6.ra-timeout:                        0 (default)
ipv6.dhcp-duid:                         --
ipv6.dhcp-iaid:                         --
ipv6.dhcp-timeout:                      0 (default)
ipv6.dhcp-send-hostname:                yes
ipv6.dhcp-hostname:                     --
ipv6.dhcp-hostname-flags:               0x0 (none)
ipv6.token:                             --
-------------------------------------------------------------------------------
proxy.method:                           none
proxy.browser-only:                     no
proxy.pac-url:                          --
proxy.pac-script:                       --
-------------------------------------------------------------------------------

Actually, we fixed it by killing the dhcclient and and reconnecting 
(nmcli con down ... and nmcli con up ... ).

We are using similar configs and everything is done by using the nmcli, 
but we are not facing similar issues there.

So at this point, I really would like to understand that behaviour.


If you have any ideas, feel free to share.


Regards,

Felix