On Thu, 16 Jan 2020 15:34:43 +0100, Stephen John Smoogen <smooge at gmail.com> wrote: > On Thu, 16 Jan 2020 at 07:58, Asle Ommundsen <aommundsen at gmail.com> > wrote: >> >> Hi, >> >> Tonight I upgraded two CentOS 8 boxes to CentOS 8.1 (1911). Then after a >> reboot of the first server the network was unavailable. In IPMI console >> everything except the network was looking good. Network was unreachable. >> No errors in NetworkManager. I also restarted NetworkManager, but it did >> not help. Then I discovered that the default gateway suddenly was >> missing. >> >> Then I rebooted the server one more time, but network was still down. >> >> Then both myself and a technician in my datcenter was debugging this (I >> had to wake him up in the middle of the night, costing me a lot of >> money), >> without finding any reason for why the default gateway was missing after >> reboot. >> >> Then we rebooted the server a third time, and all of a sudden the >> problem >> was gone and the default gateway was back. [...cut...] > In order to determine what is going on you need to give a lot more > information. > > 1. How do these boxes get their network information? DHCP or static > 2. If they are static, what controls the setting of ips: > NetworkManager or network-scripts > 3. If they are static, how are they set in > /etc/sysconfig/network-scripts/ > 4. Do the files in /etc/sysconfig/network-scripts list a GATEWAY= > 5. If you are using network-manager, what does nmtui or the graphical > tool say the gateway or default route is? Here is answers to your list. I have anonymized the some of the data: 1) Static ip configuration 2) This should be NetworkManager. nmcli output: eno1: connected to eno1 inet4 1.1.1.234/29 route4 1.1.1.232/29 route4 0.0.0.0/0 eno2: connected to eno2 inet4 192.168.0.5/24 route4 192.168.0.0/24 [root at server ~]# nmcli d show | grep IP4.GATEWA IP4.GATEWAY: 1.1.1.1.233 3) TYPE=Ethernet PROXY_METHOD=none BROWSER_ONLY=no BOOTPROTO=none DEFROUTE=yes IPV4_FAILURE_FATAL=yes IPV6INIT=yes IPV6_AUTOCONF=yes IPV6_DEFROUTE=yes IPV6_FAILURE_FATAL=no IPV6_ADDR_GEN_MODE=stable-privacy NAME=eno1 UUID=1f9ec889-3c64-470a-894b-05543ee44c29 DEVICE=eno1 ONBOOT=yes IPADDR=1.1.1..234 PREFIX=29 GATEWAY=1.1.1.233 IPV6_PRIVACY=no 4) Yes 5) [root at server ~]# nmcli d show | grep IP4.GATEWA IP4.GATEWAY: 1.1.1.233 nmtui shows the same gateway. Kind regards, Asle Ommundsen