Routing check script

[the_rock]

Hey guys,

Had customer send me this few days ago, just had chance to try it in the lab, looks pretty good. It essentially shows the hops between 2 IP addresses and also interface/default gateway used.

Below is an example:

[Expert@CP-GW:0]# ./cp_pathcheck.sh
=== Check Point Gaia: Route + Hop Path Check ===
Enter Source IP: 172.16.10.249
Enter Destination IP: 8.8.8.8

>> Routing decision for traffic FROM 172.16.10.249 TO 8.8.8.8
8.8.8.8 from 172.16.10.249 via 172.16.10.1 dev eth0
Egress interface : eth0
Next hop (via) : 172.16.10.1

>> Traceroute will use source IP: 172.16.10.249 (on eth0)

Choose traceroute probe type:
1) UDP (default)
2) ICMP (-I)
3) TCP SYN (-T) [useful if ICMP is filtered]
Select [1-3]: 2
>> Running traceroute (icmp) from 172.16.10.249 to 8.8.8.8 ...
(maxhops=30, probes=3, wait=2s)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 40 byte packets
1 172.16.10.1 2.182 ms 2.157 ms 2.156 ms
2 192.168.0.4 2.153 ms 2.191 ms *
3 173.46.3.209 2.267 ms 2.345 ms 2.443 ms
4 72.142.86.37 2.649 ms * *
5 209.148.225.133 4.121 ms * *
6 209.148.225.105 4.691 ms 2.752 ms *
7 24.156.145.98 4.031 ms * 24.156.145.98 7.595 ms
8 209.148.230.53 4.332 ms * 209.148.230.53 4.574 ms
9 * 69.63.248.69 4.753 ms *
10 * * *
11 192.178.99.39 3.983 ms * 192.178.99.39 5.542 ms
12 216.239.50.119 5.072 ms 5.119 ms 5.116 ms
13 8.8.8.8 5.280 ms 5.225 ms 5.242 ms

>> Hop summary (unique hop IPs, in order):
----------------------------------------
1. 172.16.10.1
2. 192.168.0.4
3. 173.46.3.209
4. 72.142.86.37
5. 209.148.225.133
6. 209.148.225.105
7. 24.156.145.98
8. 209.148.230.53
9. 69.63.248.69
10. 192.178.99.39
11. 216.239.50.119
12. 8.8.8.8
----------------------------------------

Done.
Tip: If hops are all * * * then ICMP/UDP may be filtered—try TCP (-T) or adjust policy.
[Expert@CP-GW:0]#

[the_rock]

Just for the context, here is the output of option 1 and 3 as well.

************************

1:

[Expert@CP-GW:0]# ./cp_pathcheck.sh
=== Check Point Gaia: Route + Hop Path Check ===
Enter Source IP: 172.16.10.249
Enter Destination IP: 8.8.8.8

>> Routing decision for traffic FROM 172.16.10.249 TO 8.8.8.8
8.8.8.8 from 172.16.10.249 via 172.16.10.1 dev eth0
Egress interface : eth0
Next hop (via) : 172.16.10.1

>> Traceroute will use source IP: 172.16.10.249 (on eth0)

Choose traceroute probe type:
1) UDP (default)
2) ICMP (-I)
3) TCP SYN (-T) [useful if ICMP is filtered]
Select [1-3]: 1
>> Running traceroute (udp) from 172.16.10.249 to 8.8.8.8 ...
(maxhops=30, probes=3, wait=2s)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 40 byte packets
1 172.16.10.1 3.324 ms 2.755 ms 3.144 ms
2 192.168.0.4 3.059 ms 2.591 ms 2.114 ms
3 173.46.3.209 2.281 ms 1.845 ms 1.605 ms
4 72.142.86.37 1.795 ms 2.390 ms 2.359 ms
5 209.148.225.133 3.447 ms 3.196 ms 3.477 ms
6 209.148.225.105 3.990 ms 3.601 ms 3.799 ms
7 24.156.145.98 5.351 ms 9.101 ms 8.964 ms
8 209.148.230.53 5.732 ms 6.557 ms 5.773 ms
9 69.63.248.69 6.184 ms 6.765 ms 5.905 ms
10 72.14.216.54 4.968 ms
* 72.14.216.54 4.994 ms
11 192.178.98.121 7.825 ms 192.178.98.117 8.107 ms 192.178.98.53 6.092 ms
12 142.251.70.13 6.573 ms 142.251.70.11 5.556 ms 216.239.40.255 6.256 ms
13 8.8.8.8 4.654 ms 6.183 ms 6.550 ms

>> Hop summary (unique hop IPs, in order):
----------------------------------------
1. 172.16.10.1
2. 192.168.0.4
3. 173.46.3.209
4. 72.142.86.37
5. 209.148.225.133
6. 209.148.225.105
7. 24.156.145.98
8. 209.148.230.53
9. 69.63.248.69
10. 72.14.216.54
11. 192.178.98.121
12. 142.251.70.13
13. 8.8.8.8
----------------------------------------

Done.
Tip: If hops are all * * * then ICMP/UDP may be filtered—try TCP (-T) or adjust policy.
[Expert@CP-GW:0]#

*********************************************

3:

[Expert@CP-GW:0]# ./cp_pathcheck.sh
=== Check Point Gaia: Route + Hop Path Check ===
Enter Source IP: 172.16.10.249
Enter Destination IP: 8.8.8.8

>> Routing decision for traffic FROM 172.16.10.249 TO 8.8.8.8
8.8.8.8 from 172.16.10.249 via 172.16.10.1 dev eth0
Egress interface : eth0
Next hop (via) : 172.16.10.1

>> Traceroute will use source IP: 172.16.10.249 (on eth0)

Choose traceroute probe type:
1) UDP (default)
2) ICMP (-I)
3) TCP SYN (-T) [useful if ICMP is filtered]
Select [1-3]: 3
>> Running traceroute (tcp) from 172.16.10.249 to 8.8.8.8 ...
(maxhops=30, probes=3, wait=2s)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 40 byte packets
1 172.16.10.1 3.351 ms 2.501 ms 2.944 ms
2 192.168.0.4 2.057 ms 14.104 ms 2.865 ms
3 173.46.3.209 1.868 ms 1.990 ms 1.523 ms
4 * * *
5 * * *
6 * * *
7 24.156.145.98 9.479 ms 9.406 ms 9.395 ms
8 209.148.230.53 12.541 ms 8.658 ms 7.847 ms
9 69.63.248.69 6.681 ms 5.839 ms 6.072 ms
10 72.14.216.54 4.288 ms 4.326 ms *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *

>> Hop summary (unique hop IPs, in order):
----------------------------------------
1. 172.16.10.1
2. 192.168.0.4
3. 173.46.3.209
4. 24.156.145.98
5. 209.148.230.53
6. 69.63.248.69
7. 72.14.216.54
----------------------------------------

Done.
Tip: If hops are all * * * then ICMP/UDP may be filtered—try TCP (-T) or adjust policy.
[Expert@CP-GW:0]#