Page MenuHomeVyOS Platform

ipv6 address drops from interface, but network still active
Open, Requires assessmentPublicBUG

Description

IP address on eth1 is assigned through dhcpv6 and a /64 passed to eth3. This is the only interface where dhcpv6 is active. Initially the ipv6 addresses display in "show interfaces" but after a few hours, disappears. The network still works as expected.

[email protected]# show interfaces
 ethernet eth0 {
     address dhcp
     description VZ
     firewall {
         in {
             name OUTSIDE-IN
         }
         local {
             name OUTSIDE-LOCAL
         }
         out {
             name OUTSIDE-OUT
         }
     }
     traffic-policy {
         out VZFiOSOut
     }
 }
 ethernet eth1 {
     address dhcp
     address dhcpv6
     description SpectrumTWC
     dhcpv6-options {
         pd 0 {
             interface eth3 {
                 sla-id 0
             }
             length 56
         }
     }
     firewall {
         in {
             ipv6-name OUTSIDE-6-IN
             name OUTSIDE-IN
         }
         local {
             ipv6-name OUTSIDE-6-LOCAL
             name OUTSIDE-LOCAL
         }
         out {
             ipv6-name OUTSIDE-6-OUT
             name OUTSIDE-OUT
         }
     }
     traffic-policy {
         out SpectrumOut
     }
 }
 ethernet eth2 {
     address dhcp
     description NaturalWireless
     firewall {
         in {
             name OUTSIDE-IN
         }
         local {
             name OUTSIDE-LOCAL
         }
         out {
             name OUTSIDE-OUT
         }
     }
     traffic-policy {
         out NWOut
     }
 }
 ethernet eth3 {
     address 172.18.50.1/24
     description NetworkTest
     ipv6 {
         address {
             autoconf
         }
     }
 }
 ethernet eth4 {
     address 10.0.0.1/16
     address fc00::1/64
     description LAN
     firewall {
         in {
             name LAN-IN
         }
         out {
         }
     }
     ipv6 {
         address {
             autoconf
         }
     }
     policy {
         route LAN-Policy
         route6 LAN-Policy
     }
 }

after a reboot, everything displays as expected:

Interface        IP Address                        S/L  Description
---------        ----------                        ---  -----------
eth0             xxx.xxx.126.54/24                  u/u  VZ
eth1             xxx.xxx.176.177/20                  u/u  SpectrumTWC
**                 2001:xxxx:xxxx:xxxx:xxxx:6c52:39d1:a695/128
**
eth2             xxx.xxx.179.69/24                  u/u  NaturalWireless
eth3             xxx.xxx.50.1/24                    u/u  NetworkTest
                 fc00::2:3eec:efff:fe01:a24f/64
                 2001:xxxx:xxxx:xxxx:xxxx:efff:fe01:a24f/64

eth4             xxx.xxx.0.1/16                       u/u  LAN
                 fc00::42a6:b7ff:fe20:4df8/64
                 fc00::1/64

but after awhile, the public ipv6 address for eth1 is no longer displayed. additionally, the public /64 prefix is no longer visible on eth3.

Interface        IP Address                        S/L  Description
---------        ----------                        ---  -----------
eth0             x.x.x.x/24                 u/u  VZ
eth1             y.y.y.y/20                  u/u  SpectrumTWC
eth2             10.12.0.221/22                    u/u  NaturalWireless
eth3             172.18.50.1/24                    u/u  NetworkTest
                 fc00::2:3eec:efff:fe01:a24f/64
eth4             10.0.0.1/16                       u/u  LAN
                 fc00::42a6:b7ff:fe20:4df8/64
                 fc00::1/64
[email protected]:~$ ping6 google.com
PING google.com(lga15s49-in-x0e.1e100.net (2607:f8b0:4006:80d::200e)) 56 data bytes
64 bytes from lga15s49-in-x0e.1e100.net (2607:f8b0:4006:80d::200e): icmp_seq=1 ttl=118 time=9.74 ms
64 bytes from lga15s49-in-x0e.1e100.net (2607:f8b0:4006:80d::200e): icmp_seq=2 ttl=118 time=13.5 ms
64 bytes from lga15s49-in-x0e.1e100.net (2607:f8b0:4006:80d::200e): icmp_seq=3 ttl=118 time=15.1 ms
64 bytes from lga15s49-in-x0e.1e100.net (2607:f8b0:4006:80d::200e): icmp_seq=4 ttl=118 time=11.5 ms

Details

Difficulty level
Unknown (require assessment)
Version
VyOS 1.4-rolling-202204162001
Why the issue appeared?
Will be filled on close
Is it a breaking change?
Unspecified (possibly destroys the router)
Issue type
Bug (incorrect behavior)

Event Timeline

I removed my comment as my issue was not a bug AFAIK, but rather a miss-configuration and operation.

@ajgnet Could you show routes after this bug?

sudo ip -6 route show
sudo ip -6 route get 2607:f8b0:4006:80d::200e