Zywall 310 not advertising default route by BGP

Emerald
Emerald Posts: 36  Freshman Member
First Anniversary 10 Comments
edited March 2022 in Security
Afternoon again.

Zywall 310 (Firmware Version:V4.71(AAAB.0) / 2022-02-22 20:44:02)

Ive now got this router up and working, running BGP all routers are communicating ok. this is all LAN side, the 310 is providing internet access to IPs inside advertised via BGP


Below screen shot see im advertising 8.8.8.8/32 & 0.0.0.0/0

The other routers get >
xxxS.inet.0: 13 destinations, 26 routes (12 active, 0 holddown, 2 hidden)
  Prefix                  Nexthop              MED     Lclpref    AS path
* 8.8.8.8/32              172.x.x.x          0                  65002 I
* 157.x.x.x/29            172.x.x.x        0                  65002 ?
  172.x.x.x/29               172.x.x.x          0                  65002 ?
* 192.168.2.0/24          172.x.x.x         0                  65002 ?
* 192.168.3.0/24          172.x.x.x          0                  65002 ?
* 192.168.25.192/26       172.x.x.x         0                  65002 ?
* 192.168.100.0/24        172.x.x.x         0                  65002 ?

So in my testing from inside hte network we can only ping 8.8.8.8 but nothing else

Then if i do this
we see this on the BGP partners >>

xxxS.inet.0: 13 destinations, 26 routes (12 active, 0 holddown, 2 hidden)
  Prefix                  Nexthop              MED     Lclpref    AS path
* 0.0.0.0/1               172.x.x.x          0                  65002 I
* 157.x.x.x/29            172.x.x.x        0                  65002 ?
  172.x.x.x/29               172.x.x.x          0                  65002 ?
* 192.168.2.0/24          172.x.x.x         0                  65002 ?
* 192.168.3.0/24          172.x.x.x          0                  65002 ?
* 192.168.25.192/26       172.x.x.x         0                  65002 ?
* 192.168.100.0/24        172.x.x.x         0                  65002 ?


And all works fine.
Obviously all though working this isnt the textbook default route.

Any ideas why routers are not recieving 0.0.0.0/0
I can do pcaps if reqd

Thanks in advance

All Replies

  • zyman2008
    zyman2008 Posts: 199  Master Member
    First Anniversary 10 Comments Friend Collector First Answer
    The BGP design of ZyWALL is to not announce the default route (0.0.0.0/0)
    It need to enable by CLI command:
    Router(config)# router bgp
    Router(config-router)# neighbor w.x.y.z default-originate
    Router(config-router)# exit
    Router(config)# write

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