Hi,

I have the following static routes setup on my laptop.
em0 is a lan connection to my router 172.26.153.1.
tun1 is sometimes used by a ssh tunnel to the same router.
It is now down.
The routing table is attached below.
Now I'm wondering why the first ping seems to use the 172.26.153/24 
route via 172.26.153.18 (which is currently not up and has priority 10) 
instead of the default route via 172.26.153.1 which has a higher 
priority and is up.
The funny thing is that adding another route to 172.26.153/24 via 
gateway 172.26.153.1 fixes this problem and allows the ping to 
happen.
Why is this route used while the default route is ignored, although it 
looks exactly the same (same priority) except having a larger subnet (0/0)??
Are more specific routes somehow preferred?


Any help, especially hints towards helpful documentation, are very 
welcome.

Christopher


$ ifconfig tun1
tun1: flags=51<UP,POINTOPOINT,RUNNING> mtu 1500
        priority: 0
        groups: tun
        status: down
        inet 172.26.153.19 --> 172.26.153.18 netmask 0xffffffff
$ route -n show -inet
Routing tables

Internet:
Destination        Gateway            Flags   Refs      Use   Mtu  Prio Iface
default            172.26.153.1       UGS       29      659     -     8 em0  
default            172.26.153.18      GS         0        0     -    10 tun1 
127/8              127.0.0.1          UGRS       0        0 33152     8 lo0  
127.0.0.1          127.0.0.1          UH         2        0 33152     4 lo0  
172.26.153.0/28    link#1             UC         1        0     -     4 em0  
172.26.153/24      172.26.153.18      GS         0        2     -    10 tun1 
172.26.153.1       00:0d:b9:24:60:40  UHLc       4       58     -     4 em0  
172.26.153.7       127.0.0.1          UG         0        0 33152    56 lo0  
172.26.153.18      172.26.153.19      H          2        0     -     4 tun1 
224/4              127.0.0.1          URS        0        0 33152     8 lo0  
$ ping -c 1 -i 1 phone
PING phone.gmerlin.de (172.26.153.17): 56 data bytes
ping: sendto: Host is down
ping: wrote phone.gmerlin.de 64 chars, ret=-1
--- phone.gmerlin.de ping statistics ---
1 packets transmitted, 0 packets received, 100.0% packet loss
$ sudo route add 172.26.153/24 172.26.153.1
add net 172.26.153/24: gateway 172.26.153.1
$ route -n show -inet                      
Routing tables

Internet:
Destination        Gateway            Flags   Refs      Use   Mtu  Prio Iface
default            172.26.153.1       UGS       13      659     -     8 em0  
default            172.26.153.18      GS         0        0     -    10 tun1 
127/8              127.0.0.1          UGRS       0        0 33152     8 lo0  
127.0.0.1          127.0.0.1          UH         2        0 33152     4 lo0  
172.26.153.0/28    link#1             UC         1        0     -     4 em0  
172.26.153/24      172.26.153.1       UGS        0        0     -     8 em0  
172.26.153/24      172.26.153.18      GS         0        3     -    10 tun1 
172.26.153.1       00:0d:b9:24:60:40  UHLc       6       87     -     4 em0  
172.26.153.7       127.0.0.1          UG         0        0 33152    56 lo0  
172.26.153.18      172.26.153.19      H          2        0     -     4 tun1 
224/4              127.0.0.1          URS        0        0 33152     8 lo0  
$ ping -c 1 -i 1 phone                     
PING phone.gmerlin.de (172.26.153.17): 56 data bytes
64 bytes from 172.26.153.17: icmp_seq=0 ttl=127 time=1.071 ms
--- phone.gmerlin.de ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/std-dev = 1.071/1.071/1.071/0.000 ms

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