Mac Server bizzare routing table

Question

My mac routing table usually is very simple.

I know it's based on bsd , but what's it doing or trying to do.

My routing table is usually very simple

however, the second one, default was point to link5 ?

Is this normal, or is this IPV6 craziness at work?

Can somehelp me understand what OSX/BSD is doing?

    nternet:
Destination        Gateway            Flags        Refs      Use   Netif Expire
default            192.168.1.254      UGSc           22        0     en1
127                127.0.0.1          UCS             0        0     lo0
127.0.0.1          127.0.0.1          UH              4    44102     lo0
169.254            link#5             UCS             0        0     en1
192.168.1          link#5             UCS             6        0     en1
192.168.1.1        0:18:39:6d:89:c5   UHLWIi          0        0     en1    739
192.168.1.189      50:ea:d6:86:26:91  UHLWIi          0        0     en1    798
192.168.1.194      127.0.0.1          UHS             0        0     lo0
192.168.1.203      5c:95:ae:dd:34:8d  UHLWIi          0        0     en1    316
192.168.1.253      a:76:ff:b5:51:79   UHLWIi          0        0     en1    911
192.168.1.254      8:76:ff:b5:51:79   UHLWIi         32      204     en1   1117
192.168.1.255      ff:ff:ff:ff:ff:ff  UHLWbI          0        7     en1

Internet6:
Destination                             Gateway                         Flags         Netif Expire
::1                                     link#1                          UHL             lo0
fe80::%lo0/64                           fe80::1%lo0                     UcI             lo0
fe80::1%lo0                             link#1                          UHLI            lo0
fe80::%en1/64                           link#5                          UCI             en1
fe80::21b:63ff:fec7:c486%en1            0:1b:63:c7:c4:86                UHLI            lo0
fe80::223:12ff:fe01:d7fe%en1            0:23:12:1:d7:fe                 UHLWIi          en1
ff01::%lo0/32                           fe80::1%lo0                     UmCI            lo0
ff01::%en1/32                           link#5                          UmCI            en1
ff02::%lo0/32                           fe80::1%lo0                     UmCI            lo0
ff02::%en1/32                           link#5                          UmCI            en1


-----------------------------------

Bizzare routing table here


Internet:
Destination        Gateway            Flags        Refs      Use   Netif Expire
default            link#5             UCS           113        0     en1
17.72.255.12       0:50:7f:5e:92:e2   UHLWIi          2        7     en1   1156
64.4.23.141        0:50:7f:5e:92:e2   UHLWIi          0        3     en1   1181
64.4.23.143        0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1189
64.4.23.147        0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
64.4.23.149        link#5             UHLWIi          0        1     en1
64.4.23.150        0:50:7f:5e:92:e2   UHLWIi          0       24     en1   1175
64.4.23.151        link#5             UHLWIi          0        1     en1
64.4.23.153        link#5             UHLWIi          0        1     en1
64.4.23.155        link#5             UHLWIi          0        1     en1
64.4.23.157        0:50:7f:5e:92:e2   UHLWIi          0        3     en1   1181
64.4.23.165        link#5             UHLWIi          0        2     en1
64.4.23.166        link#5             UHLWIi          0        1     en1
65.55.223.15       0:50:7f:5e:92:e2   UHLWIi          3       21     en1   1189
65.55.223.16       0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
65.55.223.17       0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1199
65.55.223.20       link#5             UHLWIi          0        1     en1
65.55.223.23       0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1199
65.55.223.31       link#5             UHLWIi          0        1     en1
65.55.223.32       link#5             UHLWIi          0        1     en1
65.55.223.37       0:50:7f:5e:92:e2   UHLWIi          3       21     en1   1189
65.55.223.38       link#5             UHLWIi          0        1     en1
69.163.252.33      0:50:7f:5e:92:e2   UHLWIi          1        9     en1   1181
77.67.32.254       0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1164
111.221.74.13      0:50:7f:5e:92:e2   UHLWIi          0       24     en1   1183
111.221.74.15      link#5             UHLWIi          0        1     en1
111.221.74.16      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
111.221.74.17      0:50:7f:5e:92:e2   UHLWIi          3       23     en1   1172
111.221.74.21      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
111.221.74.23      0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1172
111.221.74.24      0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1181
111.221.74.26      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1199
111.221.74.29      0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1181
111.221.74.31      link#5             UHLWIi          0        1     en1
111.221.74.37      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1190
111.221.74.38      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1199
111.221.77.141     0:50:7f:5e:92:e2   UHLWIi          0        3     en1   1199
111.221.77.144     link#5             UHLWIi          0        1     en1
111.221.77.145     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1190
111.221.77.149     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
111.221.77.154     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
111.221.77.156     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1190
111.221.77.157     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
111.221.77.162     link#5             UHLWIi          0        1     en1
111.221.77.165     link#5             UHLWIi          0        1     en1
127                127.0.0.1          UCS             0        0     lo0
127.0.0.1          127.0.0.1          UH              4    40073     lo0
157.55.56.140      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1199
157.55.56.141      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
157.55.56.143      link#5             UHLWIi          0        1     en1
157.55.56.147      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
157.55.56.148      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
157.55.56.149      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1189
157.55.56.150      link#5             UHLWIi          0        1     en1
157.55.56.157      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1172
157.55.56.158      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1175
157.55.130.143     link#5             UHLWIi          0        1     en1
157.55.130.144     link#5             UHLWIi          0        1     en1
157.55.130.145     0:50:7f:5e:92:e2   UHLWIi          0       24     en1   1181
157.55.130.152     0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1199
157.55.130.153     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1172
157.55.130.155     0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1189
157.55.130.156     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1186
157.55.130.157     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1189
157.55.130.158     0:50:7f:5e:92:e2   UHLWIi          0        3     en1   1172
157.55.130.160     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1189
157.55.130.162     0:50:7f:5e:92:e2   UHLWIi          3       21     en1   1193
157.55.130.166     link#5             UHLWIi          0        1     en1
157.55.235.141     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1193
157.55.235.142     link#5             UHLWIi          1        1     en1
157.55.235.144     0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1172
157.55.235.145     0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1172
157.55.235.149     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
157.55.235.151     link#5             UHRLWIi         0       36     en1
157.55.235.152     0:50:7f:5e:92:e2   UHLWIi          3       21     en1   1189
157.55.235.153     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1178
157.55.235.156     link#5             UHLWIi          0        2     en1
157.55.235.157     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
157.55.235.158     link#5             UHLWIi          0        1     en1
157.55.235.159     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
157.55.235.162     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1183
157.55.235.166     0:50:7f:5e:92:e2   UHLWIi          0       25     en1   1181
157.56.52.14       0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1181
157.56.52.15       0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1183
157.56.52.16       link#5             UHLWIi          0        1     en1
157.56.52.17       0:50:7f:5e:92:e2   UHLWIi          3       14     en1   1199
157.56.52.19       link#5             UHLWIi          0        1     en1
157.56.52.20       0:50:7f:5e:92:e2   UHLWIi          3       17     en1   1199
157.56.52.22       0:50:7f:5e:92:e2   UHLWIi          0       24     en1   1181
157.56.52.25       link#5             UHLWIi          0        1     en1
157.56.52.28       link#5             UHLWIi          0        1     en1
157.56.52.29       link#5             UHLWIi          0        1     en1
157.56.52.31       link#5             UHLWIi          0        1     en1
157.56.52.33       0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1189
169.254            link#5             UC              1        0     en1
169.254.174.250    127.0.0.1          UHS             1        0     lo0
169.254.255.255    ff:ff:ff:ff:ff:ff  UHLWb           0        2     en1
193.88.6.19        link#5             UHLWIi          0        1     en1
194.165.188.82     0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1166
195.46.253.211     link#5             UHLWIi          0        1     en1
204.9.163.143      0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1178
213.199.179.141    0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1172
213.199.179.142    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1165
213.199.179.143    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1166
213.199.179.146    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1172
213.199.179.147    0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1164
213.199.179.148    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1165
213.199.179.149    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1172
213.199.179.150    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1165
213.199.179.151    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1164
213.199.179.153    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1166
213.199.179.157    0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1167
213.199.179.160    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1165
213.199.179.161    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1172
213.199.179.162    0:50:7f:5e:92:e2   UHLWIi          0        2     en1   1163
213.199.179.165    0:50:7f:5e:92:e2   UHLWIi          0        1     en1   1164
213.199.179.166    0:50:7f:5e:92:e2   UHLWIi          0        3     en1   1164
224.0.0.251        1:0:5e:0:0:fc      UHmLWI          0        0     en1
255.255.255.255    ff:ff:ff:ff:ff:ff  UHLWbI          0        2     en1

Internet6:
Destination                             Gateway                         Flags         Netif Expire
::1                                     link#1                          UHL             lo0
fe80::%lo0/64                           fe80::1%lo0                     UcI             lo0
fe80::1%lo0                             link#1                          UHLI            lo0
fe80::%en1/64                           link#5                          UCI             en1
fe80::21b:63ff:fec7:c486%en1            0:1b:63:c7:c4:87                UHLI            lo0
fe80::223:12ff:fe01:d7fe%en1            0:23:12:1:d7:ff                 UHLWIi          en1
ff01::%lo0/32                           fe80::1%lo0                     UmCI            lo0
ff01::%en1/32                           link#5                          UmCI            en1
ff02::%lo0/32                           fe80::1%lo0                     UmCI            lo0
ff02::%en1/32                           link#5                          UmCI            en1

It is not normal, but it is not "IPV6 craziness at work" either. Pointing a default route directly at an interface is not a good idea because it causes the system to ARP for just about every possible destination and it won't work anyway unless there is a router on the LAN that responds to proxy ARP (which is a bad idea). But you haven't provided any information that could give any clues as to WHY your default route is pointing directly to an interface. — Celada, Sep 13 '12 at 15:21
I see some anonymous coward has marked this down already. There should be no reason why my default route is pointing to interface. Server is on DHCP just as it's in test mode. Bizzare is the word. — The Unix Janitor, Sep 13 '12 at 16:40

score 6 · Accepted Answer · answered Sep 14 '12 at 17:51

I think you're looking in the wrong place. Check your basic network settings in the Network preferences pane in System Preferences before you go looking at the raw routing tables. I'm pretty sure what you'll see is that your en1 port has a self-assigned IP address of 169.254.174.250, and no router address. The UI doesn't always explicitly indicate that it's in self-assigned mode, but the 169.254 prefix on the address is a dead giveaway. What this means is that DHCP has failed, your server wasn't assigned a proper IP address so it made one up (self-assigned), and since it doesn't have a way to make up a router address, it's in link-local mode with no router and no idea how to get off the local network.

The reason the routing table looks so weird is that, since it has no router configured, it tries to reach everything on the local network (i.e. it sends out ARP requests for every IP address it tries to reach). Something on the local network (something with the MAC address 0:50:7f:5e:92:e2) is replying to these ARP requests; it's probably a router doing some variety of ARP proxying. Because netstat -r on OS X displays the ARP table as part of the routing table, you're seeing ARP entries for every IP address your server has tried to reach.

First solution: find out what's wrong with DHCP and fix it.

Second solution: what's a server doing on DHCP anyway? Servers should almost always be statically configured, so assign it a static address (in the Network preferences pane, not with ifconfig).

Gordon, great answer :-) . Thanks for the educational post. Server was on DHCP just for testing. Everything you said is correct :-). — The Unix Janitor, Sep 14 '12 at 18:26

Mac Server bizzare routing table

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