Fwd: Re: Frequent loss of contact with ISP

[Ned Harrison]

----------  Forwarded Message  ----------

Subject: Re: Frequent loss of contact with ISP
Date: Tuesday 22 March 2005 01:15 pm
From: Bill Moran <wmoran at potentialtech.com>
To: Ned Harrison <ned.woody at cox.net>
Cc: 

[My apologies to the moderator for the traffic, but I just unsubscribed, and
 I didn't want to leave this person hanging.]

Ned Harrison <ned.woody at cox.net> wrote:
> On Sunday 20 March 2005 09:55 pm, you wrote:
> > Ned Harrison <ned.woody at cox.net> wrote:
> > > I reciently upgraded my home computer to FreeBSD 5.3 p5.  Sense then
> > > I've had minor problems connecting to my ISP.  During boot up it will
> > > sometimes freeze at the line, "Configuring syscons: keymap blanktime."
> > > or I'll lose contact with my ISP while sending an email or surfing the
> > > web. From an earlier posting to this forum I found that "Ctrl+C" will
> > > let the system finishing the boot up.  Then I can easily connect to my
> > > ISP by running "/etc/netstart" as root.
> > >
> > > Everything works fine at least for a while.  However, sooner or later
> > > I'll lose the conection again.  I have not been able to discern a
> > > pattern to the disconnects either.  Yet as soon as I run netstart again
> > > everything works again.  It can be hours before I the lose the
> > > connection or sometimes I'll lose the connection again within twenty
> > > minutes.   I've searched for a permanent fix by looking throught this
> > > forum.  But I havn't found anything yet.  Though that might be because
> > > I don't quite know how to search! :-)
> > >
> > > I am a newbie using FreeBSD so any suggestions would be appreciated.
> >
> > Spend a little time in the /var/log directory and see if anything is
> > being logged around the time you lose connection.
> >
> > Also, more clearly defining "lose connection" would help.  What does
> > ifconfig say when the connection is up and when it's down?  The
> > difference between those two outputs may lead you toward a solution.
>
> Thank you for the suggestions.  I've scanned the log files and didn't see
> any unusual error messages.  But that could be because I don't know what to
> look for.  I've run FreeBSD for just about one year and had no Unix
> experience prior to that at all.  I jumped from Windows, where somebody did
> everything for me to, FreeBSD where I have to figure things out on my own
> with only hints and suggestions. (Honestly, I find it funner this way!) 
> I'll check to logs next time it goes down.
>
> I copied the results from ifconfig when everything is working to a file. 
> As soon as I "lose the connection" I'll run ifconfig again.
>
> To get more defined regarding the loss of connection, it's almost as if I
> typed "ipfw flush" as root and cut myself down to the default "deny
> everything" rule.  Sent emails will set unprocessed in the queue, when
> attempting to download e-mail, K-mail will return an unknown host error
> message,  web browsers will either open to a blank white page or give me an
> invalid ULR error message.  It even went down while viewing a video on
> Xine. The video just stopped, then I got an "invalid host" error message. 
> As soon as I type /etc/netstart.  Boom! everythings up an running as if
> nothing was ever wrong.

I saw your other email as well, which shows that ifconfig during up/down is
the same.  That means that you're not losing your IP address, and the fact
that /etc/netstart fixes the problem probably means it's not hardware
related.

So the next steps are to tear apart the networking system and figure out
exactly which part of it is shutting off.  First, do these:

1) Copy /etc/resolv.conf to your home dir: this contains your DNS
   server information.
2) Save the output of `netstat -rn` (use something like
   `netstat -rn > /home/<username>/netstat.txt`  This is your routing
   table.

Now ... the next time it goes down, check:
1) Did /etc/resolv.conf change?
2) Did the output of `netstat -rn` change?
3) In the netstat output will be a line that starts with "default", see
   if you can ping that IP address - if not, then the problem is probably
   with your switch/hub or other local network.
4) Try pinging 206.190.36.122 (that's the ip for story.news.yahoo.com),
   if it works, then the problem is likely with DNS.
5) if #4 works, try pinging story.news.yahoo.com ... if that fails, then
   DNS is almost certainly the problem, if that works, then the problem
   is somewhere in the network config, or application config.

--
Bill Moran
Potential Technologies
http://www.potentialtech.com

-------------------------------------------------------

Thanks for the help.  I believe you are correct in that it's probably not a 
hardware issue.  I dual boot with Linux and I am having no problems 
connecting to the internet on that side. 

System didn't go down Wednesday, but it went down today.  The output of 
netstat -rn didn't change.   I tried to ping the IP address after the word 
default in line 3.   Here is the output:

nedsbsd# ping -a -c 3 -o 68.13.118.1
PING 68.13.118.1 (68.13.118.1): 56 data bytes
ping: sendto: Permission denied
ping: sendto: Permission denied
ping: sendto: Permission denied

--- 68.13.118.1 ping statistics ---
3 packets transmitted, 0 packets received, 100% packet loss

However, when I ran /etc/netstart and tried it again I got the same result.

I don't have a local network or hub or switch.  So could the problem be with 
my ISP?  I will try the ping command the Linux side to see what I get.

After that I'll  pull out the holy water, incense, and rubber chicken to see 
if that will help!

Thanks,
Ned