Re: route table behind router
Andrei Popescu a écrit :
> On Vi, 11 feb 11, 19:20:40, Mike McClain wrote:
>> root@/deb40a:~> wget -v google.com
>> --16:28:14-- http://google.com/
>> => `google.com/index.html'
>> Resolving google.com... 74.125.227.20, 74.125.227.16, 74.125.227.17, ...
>> Connecting to google.com[74.125.227.20]:80... failed: Connection timed out.
>> Connecting to google.com[74.125.227.16]:80... failed: Connection timed out.
>> Connecting to google.com[74.125.227.17]:80... failed: Connection timed out.
>
> Hmm, is the router using PPPoE to connect to your ISP? Try this:
>
> ifconfig eth0 mtu 1400
MTU issues should only affect "big" packets containing data, not the
establishement of the connection. But it is worth the try. Adapt the
interface name to the one connected to the router.
At this point, I have two ideas : either a problem with TCP connections
or specifically with HTTP connections. I would first try to connect to
other TCP-based services such as SMTP, POP3, FTP... If it fails too,
then the problem is with TCP, likely with some TCP option not supported
by the router or the ISP. The usual suspects are window scaling,
timestamps, ECN, SACK, which can be enabled or disabled via sysctl
variables in /proc/sys/net/ipv4/. Try to enable and disable each of them
and see what happens.
You can also use tcpdump to capture the packets on the interface while
trying to connect.
Another useful tool is tcptraceroute, it can help to see where something
wrong happens.
Reply to: