7 Replies Latest reply on Feb 27, 2018 10:28 AM by Tomas Greno

    7.4 Route Problem

    user3334331

      After updating Oracle Linux 7.3 to 7.4 the device route for the subnet disappears.  Everything on the same subnet then gets routed to the gateway instead of using a direct connection from the NIC.

       

      Route table on a 7.3 server (ip route show dev ens160):

      default via 192.168.111.1  proto static  metric 100

      192.168.111.0/24  proto kernel  scope link  src 192.168.111.85  metric 100

       

      You can see all subnet traffic routed to then link not the gateway.

       

      Route table after upgrading to 7.4 and rebooting:

      default via 192.168.111.1 proto static metric 100

       

      Now I am missing the subnet route.

       

      We can add a static route but we have never needed to do this before.  Is this a problem with the updated net manager or a change?  I reviewed the release notes and I do not see anything about a functionality change in networking routes.

      Thanks,

      Mike

        • 1. Re: 7.4 Route Problem
          Tomas Greno

          Hi,

           

          I was facing exactly the same issue during last OS update on multiple database server clusters.

          Probably some NetworkManager.service bug. After disabling NetworkManager.service is everything working again.

           

          Check your network interface scripts for NM_CONTROLED parameter:

          /etc/sysconfig/network-scripts/ifcfg-*

          NM_CONTROLLED=no

           

          It should be set to "no" or missing (default is "no")

          After that you can stop and disable NetworkManager.service

           

          [root@xxxx ~]# systemctl stop NetworkManager.service

          [root@xxxx ~]# systemctl disable NetworkManager.service

          [root@xxxx ~]# service network restart    --->    invoke reload of ip network related scripts

          [root@xxxx ~]# route -n    --->    routes for local subnets are added automatically

           

          I would try to re-enable NetworkManager.service after next OS update. Maybe it will be fixed in the meantime.

           

          Regards,

          Tomas

          • 2. Re: 7.4 Route Problem
            puk

            I came across this exact same problem this week patching a large number of 7.2 servers.  I tested a few first but never noticed the issue as I was accessing them from outside the main subnet, so going via the gateway and this still works, but when I did the main update this week all of our build servers broke, because yes they are on the same subnet.  So now they try and go via the gateway which doesn't work, so I had to add the route in manually.

            What makes it worse is that when I reboot, even doing the persistent routes with route-interface files, it still doesn't apply as I get this in the messages log.

             

            NetworkManager[952]: <error> [1511292782.5643] platform-linux: do-add-ip4-address[2: 10.10.10.20/24]: failure 17 (File exists)

            NetworkManager[952]: <error> [1511292782.5646] platform-linux: do-add-ip4-route[2: 0.0.0.0/0 100]: failure 101 (Network is unreachable)

            NetworkManager[952]: <warn> [1511292782.5648] default-route: failed to add default route 0.0.0.0/0 via 10.10.10.254 dev 2 metric 100 mss 0 rt-src user with effective metric 100

             

            So yes to me this looks like NetworkManager causing the issue.  We are going to hold off upgrading to 7.4 because of this but will keep an eye on it.  How do we go about letting Oracle know about a possible bug?

            • 3. Re: 7.4 Route Problem
              Tomas Greno

              My next update of the OS packages is planned for march/april, I think.

              Please let me know version of your NetworkManager package.

              I can make a test in the meantime if it is fixed or not with the latest package.

              • 4. Re: 7.4 Route Problem
                2bb21a03-6022-4b75-81ed-a6aae4871e25

                We are seeing the same problems on an AWS instance.

                Installed package is:

                 

                NetworkManager-1.8.0-11.el7_4.x86_64

                • 5. Re: 7.4 Route Problem
                  Tomas Greno

                  Hi all,

                   

                  after updating to NetworkManager-1.8.0-11.el7_4.x86_64 problem disappear.

                  I was able to start NetworkManager service again and all routes were applied as expected.

                   

                  Regards,

                  Tomas

                  • 6. Re: 7.4 Route Problem
                    TakeTheLongPath

                    It's a month after you posted this, I have this RPM version installed and I still have the issue.

                     

                    rpm -qa NetworkManager

                    NetworkManager-1.8.0-11.el7_4.x86_64

                     

                    What makes matters worse for me is my VMs are sitting between two switches as we migrate. The old switch somehow handles the requests and connects the two machines on the same subnet that want to talk. The new switch does not... So that's a second issue for me to look into.

                    • 7. Re: 7.4 Route Problem
                      Tomas Greno

                      can you upload network configuration scripts for your public and interconnect interfaces?