Comments on: how do i find my router’s external ip address? http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/ Fri, 10 Feb 2012 05:54:57 +0000 hourly 1 http://wordpress.org/?v=3.3 By: david carlton http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4604 david carlton Fri, 12 May 2006 05:23:59 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4604 As Per pointed out, ssh also knows the answer: <code>ssh HOSTNAME 'echo $SSH_CLIENT'</code> does the trick. As Per pointed out, ssh also knows the answer: ssh HOSTNAME 'echo $SSH_CLIENT' does the trick.

]]> By: david carlton http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4589 david carlton Wed, 03 May 2006 00:32:47 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4589 Thanks, I'd read about dyndns in my router's documentation but hadn't realized it was free. Hmm; maybe I will give that a try. In the meantime, your scripts do exactly what I want. I've taken your idea of using http and modified it somewhere: I'm instead looking up a nonexistent web page on the remote host where I'm storing my IP address (to avoid relying on two different hosts), and grepping through the Apache log to find where I connected from. Works like a charm. Thanks, I’d read about dyndns in my router’s documentation but hadn’t realized it was free. Hmm; maybe I will give that a try.

In the meantime, your scripts do exactly what I want. I’ve taken your idea of using http and modified it somewhere: I’m instead looking up a nonexistent web page on the remote host where I’m storing my IP address (to avoid relying on two different hosts), and grepping through the Apache log to find where I connected from. Works like a charm.

]]> By: Praveen http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4584 Praveen Tue, 02 May 2006 12:47:05 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4584 Just curious to know if that was helpful at all? :-) Just curious to know if that was helpful at all? :-)

]]> By: Praveen http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4537 Praveen Mon, 01 May 2006 09:48:00 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4537 I also wanted to tell you about the free DNS service provided by http://www.dyndns.com. Once you have registered a free account with them, you have an option to create an entry for your host with a good number of options of firstlevel domain names like dyndns.org, homelinux.net, etc. Once you have created the host entry, you could use the following script to update the records from your cron or whatever. <code>#!/bin/bash # Set the username and password for the dyndns account USERNAME= PASSWORD= # Set the system being used to either static or dynamic DNS SYSTEM=dyndns # Set the hostname for the record to change DYNHOST= # Set whether to wildcard the DNS entry, i.e. *.$DYNHOST WILDCARD=OFF ############################################ ## DO NOT EDIT ANYTHING BEYOND THIS POINT ## ############################################ if [ -z "$DYNDNS" ]; then DYNDNS="$DYNHOST" fi if [ -z "$DNSWILD"]; then DNSWILD="$WILDCARD" fi LOOKUP=`host $DYNHOST | cut -f3` MYIP=`curl -s http://checkip.dyndns.org | awk '{print $6}' | awk ' BEGIN { FS = "<" } { print $1 } '` # Do the work if [ "$LOOKUP" = "$MYIP" ]; then echo "No change in DNS entry." else echo `lynx -auth=${USERNAME}:${PASSWORD} -source "http://members.dyndns.org:8245/nic/update?system=${SYSTEM}&hostname=${DYNDNS}&myip=${MYIP}&wildcard=${DNSWILD}"` fi</code> I also wanted to tell you about the free DNS service provided by http://www.dyndns.com. Once you have registered a free account with them, you have an option to create an entry for your host with a good number of options of firstlevel domain names like dyndns.org, homelinux.net, etc. Once you have created the host entry, you could use the following script to update the records from your cron or whatever.

#!/bin/bash
# Set the username and password for the dyndns account
USERNAME=
PASSWORD=
# Set the system being used to either static or dynamic DNS
SYSTEM=dyndns
# Set the hostname for the record to change
DYNHOST=
# Set whether to wildcard the DNS entry, i.e. *.$DYNHOST
WILDCARD=OFF
############################################
## DO NOT EDIT ANYTHING BEYOND THIS POINT ##
############################################
if [ -z "$DYNDNS" ]; then
DYNDNS="$DYNHOST"
fi
if [ -z "$DNSWILD"]; then
DNSWILD="$WILDCARD"
fi
LOOKUP=`host $DYNHOST | cut -f3`
MYIP=`curl -s http://checkip.dyndns.org | awk '{print $6}' | awk ' BEGIN { FS = "<" } { print $1 } '`
# Do the work
if [ "$LOOKUP" = "$MYIP" ]; then
echo "No change in DNS entry."
else
echo `lynx -auth=${USERNAME}:${PASSWORD} -source "http://members.dyndns.org:8245/nic/update?system=${SYSTEM}&hostname=${DYNDNS}&myip=${MYIP}&wildcard=${DNSWILD}"`
fi

]]> By: Praveen http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4536 Praveen Mon, 01 May 2006 09:02:32 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4536 Alternatively there is another site that provides text output to avoid all the 'awk'ing business. But I felt that dyndns is more reliable than other guys. <code>#!/bin/bash curl "http://www.networksecuritytoolkit.org/nst/cgi-bin/ip.cgi" </code> Alternatively there is another site that provides text output to avoid all the ‘awk’ing business. But I felt that dyndns is more reliable than other guys.

#!/bin/bash
curl "http://www.networksecuritytoolkit.org/nst/cgi-bin/ip.cgi"

]]> By: Praveen http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/comment-page-1/#comment-4535 Praveen Mon, 01 May 2006 08:57:13 +0000 http://malvasiabianca.org/archives/2006/04/how-do-i-find-my-routers-external-ip-address/#comment-4535 David, may be the shell script that I use can help you. <code>#!/bin/bash curl -s http://checkip.dyndns.org | awk '{print $6}' | awk ' BEGIN { FS = "<" } { print $1 } ' </code> David, may be the shell script that I use can help you.

#!/bin/bash
curl -s http://checkip.dyndns.org | awk '{print $6}' | awk ' BEGIN { FS = "<" } { print $1 } '

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