Description

Router to Conductor connectivity lost after reboot, forwarding traffic unaffected.

Symptoms

From the GUI, the router status shows "Disconnected"

Test connection fails

 

From the Router's Linux prompt, run the following command.

Get the conductor IP from /etc/128technology/global.init


nc -vz <conductor_IP> 930

[root@ar50230080 ~]# nc -vz 10.219.61.237 930

No route to host..

 

Expected Output

[root@ar50230080 ~]# nc -vz 10.219.61.237 930

Ncat: Version 7.50 ( https://nmap.org/ncat )

Ncat: Connected to 10.219.61.237:930.

Ncat: 0 bytes sent, 0 bytes received in 0.01 seconds.

Solution

If the Router is managed via Linux interface, then a default route will be created, which will be used for management.

 

Example:

[root@ar50230080 ~]# ip route

default via 10.219.61.1 dev ens192 proto static metric 100 

10.219.61.0/24 dev ens192 proto kernel scope link src 10.219.61.224 metric 100 

169.254.0.0/16 dev kni254 scope link metric 1007 

169.254.127.126/31 dev kni254 proto kernel scope link src 169.254.127.127 

[root@ar50230080 ~]#

 

If the Router is managed via the SSR Forwarding interface, then a kni254 route is expected to be present in Linux; without that, the router can't reach the conductor.

 

Example: (expected)

[root@ar50230080 ~]# ip route

default via 169.254.127.126 dev kni254 metric 20 

10.219.61.0/24 dev ens192 proto kernel scope link src 10.219.61.224 metric 100 

169.254.0.0/16 dev kni254 scope link metric 1007 

169.254.127.126/31 dev kni254 proto kernel scope link src 169.254.127.127 

[root@ar50230080 ~]#

 

Sometimes, the Linux interface configured becomes down or inactive, and at the same time, the kni254 default route may be missing. When no active default route is configured, the Router will not be able to connect to the conductor. If the Linux interface is down, then either remove the interface from Linux or deactivate the route by commenting out the below config.

 

ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state DOWN group default qlen 1000

link/ether 00:50:56:a9:2e:db brd ff:ff:ff:ff:ff:ff

inet 10.219.61.224/24 brd 10.219.61.255 scope global noprefixroute ens192

valid_lft forever preferred_lft forever

 

[root@ar50230080 ~]# vi /etc/sysconfig/network-scripts/ifcfg-ens192

# Created by 128T-hardware-bootstrapper

BOOTPROTO=dhcp

DHCPRELEASE=yes

#DEFROUTE=yes

#IPADDR=10.219.61.224

#NETMASK=255.255.255.0

DEVICE=ens192

 

#Deactivate the interface if not in use.

 [root@ar50230080 ~]# ifdown ens192

 

Then manually add a default route to kni254 if it's missing.

 [root@ar50230080 ~]# ip route add default via 169.254.127.126 dev kni254 metric 20  

 

Since now we have disabled the default route from the Linux interface, the kni254 route should be auto-created during the next reboot.

 

Modification History

2025-09-25 : Article Created