Can't traceroute on Mac?

[Collected]

Very odd problem..

Today I felt access to a particular website was rather slow, so I decided to do a traceroute to the site in question to see if my ISP had a routing issue.

However all I get is * * * on every hop including the 1st one. It doesn't get anywhere at all. Just time out, time out, time out.

So I tried ping.. ping works fine. It resolves the DNS, and the ping is returned with no problems. I can load plenty of websites, including this one.

So I fired up my windows box that is on the same network, same router.. traceroute works fine to the same sites.

What is even more strange is I can traceroute over a VPN to my machine at work.. but traceroutes to sites that work on my windows box fail to work on my mac.

Any suggestions? Thank you. Probably something simple but I can't work out what's causing it.

 

[wrldwzrd89]

It's got to be a networking setting on your Mac somewhere. First thing I'd check is the firewall settings. Then, make sure everything looks right in the Network pane of System Preferences.

 

[MacTribe]

Try set up a 2nd test account on your Mac then traceroute from there. Also make sure you try in both 'network utility' and 'terminal' and lastly make sure you've done all the obvious things like restarting the machine, router, switches etc and checked you have the correct network settings under 'System Preferences'

 

[Collected]

Checked my network settings. It's DHCP over wireless so no real configuration has ever been done. It did it itself when I connected to my wireless router. Firewall is turned off. It does the same thing if I run the traceroute from the network utility and terminal. Rebooted router and mac. I've not setup a new user tho, that's the only thing left to try.

Here is an example:

traceroute to www.macrumors.com (74.86.132.180), 64 hops max, 52 byte packets
1 * * *
2 * * *
3 * * *

PING www.macrumors.com (74.86.132.180): 56 data bytes
64 bytes from 74.86.132.180: icmp_seq=0 ttl=46 time=145.458 ms
64 bytes from 74.86.132.180: icmp_seq=1 ttl=46 time=142.007 ms
64 bytes from 74.86.132.180: icmp_seq=2 ttl=46 time=142.298 ms

So ping works.. but traceroute doesn't want to. Very odd. I'll update if I ever find the cause. Thank you for the suggestions.

 

[jlg89]

Possible solution

Usually, when pings work but traceroutes don't, it's because some or all ICMP traffic is being blocked somewhere. Be sure your local firewall is configured to at least allow "ICMP required types."

 

[satcomer]

Usually, when pings work but traceroutes don't, it's because some or all ICMP traffic is being blocked somewhere. Be sure your local firewall is configured to at least allow "ICMP required types."

I bet IMCP is blocked by his firewall or his/her's Internet router.

 

[Eric Lee]

Hi,

Usually, when pings work but traceroutes don't, it's because some or all ICMP traffic is being blocked somewhere. Be sure your local firewall is configured to at least allow "ICMP required types."

So ping works.. but traceroute doesn't want to. Very odd.

So I fired up my windows box that is on the same network, same router.. traceroute works fine to the same sites.

Under Windows traceroute uses ICMP while under Unix traceroute uses UDP. If something is filtering UDP packets, the Window traceroute will work when a Unix traceroute won't. Also note that ping uses TCP so there's no connection to traceroute not working. Modern firewalls will kill random UDP traffic (not IMCP!), since it got abused in the past (Windows botnets come to mind).

This thread is somewhat old but if you run into this kind of problem:

Open terminal and copy&paste the following command and hit enter to see if a ICMP tracert works:

traceroute -P icmp 217.72.205.202

Best regards,
Eric