Strange dsl problems

[Craig White]

On Tue, 2008-03-04 at 19:27 -0600, Josef Lowder wrote:
> .
> Recently, I have been experiencing strange dsl problems, 
> which I have been unable to either solve or even pin down. 
> 
> My main Linux box which is ethernet wire connected to my 2-wire 
> modem/router has had a few dropped signals, but that is minor. 
> 
> My backup Linux box which is also ethernet wire connected through 
> a hub to the same router has lost the connection entirely. 
> 
> My IBM Thinkpad in another room has generally remained connected 
> via a 3-com wireless PCI card, though it sometimes drops the 
> signal; but when that happens I can always quickly reconnect. 
> 
> On my HP zv6000 laptop I have a dual-boot Linux partition and a 
> win-xp partition.  I have never been able to get the internal 
> broadband 802.11 wireless card to work with the Linux partition, 
> but until recently, I have never had any problem maintaining a 
> steady 54Mbps wireless connection.  But now that has gone flakey. 
> However, I can connect to my neighbor's linksys unsecured wireless 
> router at 11Mbps. 
> 
> On my wife's computer in another room dual booting Linux and win-xp 
> I initially had a wireless connection on the Linux partition, but 
> it failed shortly after I set it up, so she has been using the xp 
> partition and has maintained a steady 54Mbps connection ... until 
> recently, but that connection has become unreliable.  Sometimes 
> it works and sometimes it doesn't. 
> 
> Today, I called both 2-wire and qwest, but neither were able to 
> help me solve the problem. 
> 
> I've tried ipconfig on the xps and /sbin/ifconfig on the linux 
> boxes and get a mixed bag of IP addresses. 
> 
> So I'm stuck.  How can I solve this? 
----
there really shouldn't be any dropped signals. I would be concerned with
that.

The next question is where are the breaks in the signals?

for example, 

this is pinging cox dns server...
# ping -c 4 68.2.16.30
PING 68.2.16.30 (68.2.16.30) 56(84) bytes of data.
64 bytes from 68.2.16.30: icmp_seq=1 ttl=56 time=12.5 ms
64 bytes from 68.2.16.30: icmp_seq=2 ttl=56 time=11.3 ms
64 bytes from 68.2.16.30: icmp_seq=3 ttl=56 time=19.7 ms
64 bytes from 68.2.16.30: icmp_seq=4 ttl=56 time=15.2 ms

--- 68.2.16.30 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3000ms

Note, no packet loss...no drops

if there were drops...I would first ping my router, then ping the
gateway address of the router and so on.

You can figure things out by doing a traceroute, like this...

# traceroute -n 68.2.16.30
traceroute to 68.2.16.30 (68.2.16.30), 30 hops max, 40 byte packets
 1  192.168.2.254  4.638 ms  4.924 ms  5.360 ms   <- my router
 2  68.230.64.1  26.181 ms  26.367 ms  26.531 ms  <- the router gateway
addr
 3  68.2.6.177  22.060 ms  22.437 ms  22.609 ms   <- cox routing table
 4  68.2.12.90  60.387 ms  60.762 ms  60.932 ms   <- cox routing table
 5  68.2.12.9  28.370 ms  29.649 ms  29.821 ms    <- cox routing table
 6  68.2.12.5  33.068 ms  28.813 ms  28.433 ms    <- cox routing table
 7  68.2.12.1  28.647 ms  16.119 ms  16.132 ms    <- cox routing table
 8  68.2.14.1  16.225 ms  17.195 ms 68.2.14.13  24.698 ms
 9  68.2.16.30  16.425 ms  19.136 ms  17.356 ms

this type of action helps your figure out where the problem is

Craig