03-12-2010 11:39 AM - edited 03-06-2019 10:07 AM
I have a 2800 router that works just fine with about 50 PCs and 1 other Mac. When I connect the new iMac 27" to my network I can't get to the internet. It shows all the correct addresses and can see everything on my LAN, but can't see out past the router. If I put a cheap netgear router between the iMac and the 2800 and double NAT, I can get to the internet. What could be wrong with the router, or iMac? Could there be a firmware update for the router? All of the updates for the iMac have been applied, and it's running 10.2.6. Any ideas? Thanks.
03-16-2010 08:12 AM
Richard,
I assume you meant OS X 10.6.2
When you have your iMac connected to the 2800, does it show a default gateway in its routing table?
Run this command on a terminal session on the iMac:
netstat -rn
and see if there is an entry that states "default" with the IP address of your router.
For example:
% netstat -rn
Routing tables
Internet:
Destination Gateway Flags Refs Use Netif Expire
default 192.168.1.1 UGSc 147238 0 en0
03-16-2010 11:55 AM
Yes, i ment OS X 10.6.2.
When I run the netstat -rn the gateway is shown, and it is the correct address for the router.
To get the system running and working on my network I have it conntect to a wireless router that routes through the 2800 to get her internet access, and have the wired connection on a static manual ip without the gateway address. It lets me see our internal network and gives us internet access for now.
I appreciate your help. Any other ideas?
03-16-2010 11:59 AM
With the iMac not connected to the wireless network and after verifying that the default route points to the 2800, can you do a traceroute to some address on the Internet and post the results here?
03-19-2010 10:16 AM
Sorry it took so long to get back in here. I tried the traceroute and it failed. I can ping other computers and I can ping the router. Any other ideas or things to try?
03-19-2010 10:17 AM
What do you mean by "it failed"?
Can you please post the output of the traceroute?
03-19-2010 10:37 AM
Traceroute: unknown host www.cnn.com
03-19-2010 10:49 AM
Try tracerouting to an IP address rather than a hostname.
For example, traceroute 157.166.226.26
03-19-2010 01:18 PM
Not sure if you saw my reply, so I'lll post it again.
Rose-Horenskys-iMac:~ rosehorensky$ traceroute 157.166.226.26
traceroute to 157.166.226.26 (157.166.226.26), 64 hops max, 52 byte packets
1 192.168.1.221 (192.168.1.221) 1.226 ms 0.879 ms 0.745 ms
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
^C
03-19-2010 10:43 AM
Make sure the Airport wireless card is turned off.
03-19-2010 11:27 AM
Yes, I turn off the air card, and turn on dhcp on the wired for each of the tests. With the air card on, everything works just fine. Here are the results from using the ip for cnn.com. I stopped it after 14 hop tried.
Rose-Horenskys-iMac:~ rosehorensky$ traceroute 15.166.226.26
traceroute to 15.166.226.26 (15.166.226.26), 64 hops max, 52 byte packets
1 192.168.1.221 (192.168.1.221) 0.985 ms 1.026 ms 0.818 ms
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
^C
03-19-2010 11:50 AM
Sorry, I mistyped on my traceroute, but have the same results.
Rose-Horenskys-iMac:~ rosehorensky$ traceroute 157.166.226.26
traceroute to 157.166.226.26 (157.166.226.26), 64 hops max, 52 byte packets
1 192.168.1.221 (192.168.1.221) 1.226 ms 0.879 ms 0.745 ms
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
^C
03-19-2010 02:10 PM
can you ping external IP addresses? try a ping to 4.2.2.2 - if that responds try a traceroute to 4.2.2.2 with the -n flag
03-22-2010 08:10 AM
No, can't ping to anything outside the local network, even dns addresses. I can't see beyond the Cisco router using the wired adapter. Don't give up guys. There has to be some crazy reason for this. Any idea what the packets look like coming from the iMac? Does Snow Leopard do something new and fancy or strange?
03-22-2010 08:33 AM
can you post the config of the 2800?
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