Re: Troubleshooting connection loss (novice question)

On Mon, 29 Oct 2007 22:09:28 GMT, Allen Weiner wrote:

(I don't know what SWAG stands for).

Such a Wild A$$ Guess

About DHCP lease, I power off my
DSL modem every day at the end of a session. The loss of connection
tends to occur about two hours into the session. (Wondering about a
misbehaving cron job.).After the failure occurs,

Still not happy not knowing how long the lease is in the modem.

I'm unable to access
the modem. (Firefox: browse http://192.168.1.1)

You should be able to get to the modem web page even if it lost it's
connection to ISP. First time you have a connection, verify you can
ping -c 1 192.168.1.1



======== chkconfig --list ==========
Double check if /avahi/ needs to be disabled on boot
avahi-daemon 0:off 1:off 2:off 3:on 4:on 5:on 6:off

Stop those avahi deamons from booting. You do not need them.

======== grep -v '^#' /etc/resolv.conf ==========
; generated by /sbin/dhclient-script
search myhome.westell.com
nameserver 192.168.1.1
nameserver 192.168.1.1

I would delete the search line to speed up DNS lookups.
and change the second nameserver to a public one if me.

======== hostname ==========
localhost.localdomain

Well, some deamons like to have a Full Qualified Domain Name (FQDN).
You created one, but I would not have picked localhost as a node name.

If you have not registered a domain name you can make one up and add
..invalid to it. Example nodes from my /etc/hosts

192.168.1.132 wb.home.invalid wb
192.168.1.31 wb7_0.home.invalid wb7_0
192.168.1.11 fw.home.invalid fw
192.168.1.12 wb1.home.invalid wb1




======== cat /etc/sysconfig/network ==========
NETWORKING=yes
HOSTNAME=localhost.localdomain

Here is where you can set your FQDN node name. Example:
HOSTNAME=wb.home.invalid

or
HOSTNAME=darkstar.nowhere.invalid


============== head -15 /etc/hosts ===============


Well that bites. and can cause problems.
That hosts file need fixing. At best is should be

127.0.0.1 localhost.localdomain localhost

Give your node a FQDN and it would look something like
127.0.0.1 darkstar.nowhere.invalid darkstar localhost


Ok, If it were me, I would set eht0 up as static so you know it can
talk to the Cable modem regardless if the modem does not hand out a
lease to your system. No sense fighting more than one thing at a time.

For trouble shooting, once you know physical connection is working you
ping each item in the path to the internet.

The mii-tool -v eth0 shows you if link is ok and nic shook hands with
whatever it is connected to. Now you know the physical connection is good.

After ping yahoo's ip works you test DNS by pinging by name. Each ping has to
work to do the next step. Example for your system

ping -c 1 localhost # checks ping is working

ping -c 1 $(hostname -s) # pings your node name
# proves dns uses hosts file

ping -c 1 lan_gateway_ip_here # use gateway ip found in route -n
# yea, can access modem

ping -c 1 ISP_gateway_ip_here # you have to look in modem to find it
# yea, can access ISP's network

ping -c 1 66.94.234.13 # yahoo is up
# ISP is open to internet.

ping -c 1 yahoo.com # if works, dns is working


You might get ip addies for somewhere besides yahoo just incase.
.

Relevant Pages

  • Re: Troubleshooting connection loss (continued)
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    ... Did the Comcast tech look at signal strength from modem ... both when connection is working and has failed. ... One indication of a bad attitude is no numbers taken when ... did same thing using ping from subscriber side - and collected numbers ...
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