My isp provides dynamic ip addresses.I have forwarded my port to an raspberry pi and accessing it through ssh and also using it as web server.but the problem is that ip changes every 3-4 days is there any way or script so that i can be informed or updated with new ip address.
Thank You.
You can write a script like:
============
#!/bin/bash
OUT=$(wget http://checkip.dyndns.org/ -O - -o /dev/null | cut -d: -f 2 | cut -d\< -f 1)
echo $OUT > /root/ipfile
============
Set a cron to execute this every 3h or something and configure your mta to send the file /root/ipfile to your email address ( that too you can use a cron ). mutt can be a useful tool to attach the file and do the email delivery.
Related
I can't find anything that helps with this issue even if the answer may be very simple.
I'm trying to get squid to redirect traffic through a 3g dongle, therefore I need to table the IP and change it in the squid.conf every time it changes.
I'm using this code here on "/etc/ppp/ip-up.local" so it's launched every time a new IP connects (or reconnects) to the machine.
#!/bin/bash
if [[ "$PPP_IFACE" == "ppp0" ]] ; then
TABLE=uplink2
/bin/sed -i "s&\(tcp_outgoing_address\).*\(very1\)&\1 $PPP_LOCAL \2&" /etc/squid/squid.conf
fi
##generate ip subnet for route
baseip=`echo "$PPP_LOCAL" | cut -d"." -f1-3`
/usr/sbin/ip route add "$baseip".0/24 dev "$PPP_IFACE" src "$PPP_LOCAL" table "$TABLE"
/usr/sbin/ip route add default via "$PPP_REMOTE" table "$TABLE"
/usr/sbin/ip rule add from "$PPP_LOCAL" table "$TABLE"
/usr/sbin/squid/ -k reconfigure
/usr/bin/systemctl squid restart
exit 0
The problem is that baseip=echo "$PPP_LOCAL" | cut -d"." -f1-3 cannot use $PPP_LOCAL
I tried to add echo $PPP_LOCAL >> file.txt but it just adds an empty line.
It's awkward to me that sed instead accesses the variable and modify correctly the squid.conf file with the new address
How can I fix this??
I also have a "sub-question", I'm a complete newbie just starting to learn and I'm not sure whether or not I should add an ip-down code to remove the table rules
Thanks everyone for the help
I was thinking about syntax looking like this:
IP: 123.123.123 | 28.10.2016 17:24 | root#vps:~$
Is it possible?
I wish log bash history with this data for debugging and backup.
I was try on it, but time is static and I don't know how write IP:
echo "force_color_prompt=yes" >> /root/.bashrc
echo "PS1='$(date +%T) | ${debian_chroot:+($debian_chroot)}\[\033[01;31m\]\u#\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '" >> /root/.bashrc
Maybe IP can be printed only first time after SSH login, is it possible?
Thanks
For IP getting printed out, add following lines to your .bashrc:
ip=`ip a | grep wlan0 | grep -oE "\b([0-9]{1,3}\.){3}[0-9]{1,3}\b" | head -1`
echo $ip
unset $ip
Now when ever you open a new terminal, your will get ip printed out for you. Same goes for ssh.
Please notice that Im using my wlan0 adapter to get the ip, you may need to change that to eth0 depending on your environment.
Set ip with Farhad's answer, then:
PS1='IP: $ip | \D{%d.%m.%G %H:%M} | \u#\h:\W$'
The time is dynamic.
References
Controlling the Prompt - Bash Reference Manual
STRFTIME(3) - Linux Programmer's Manual
I would like to trigger a service when a change of an ip address on a specific interface occurs. Is there a target for this or some other method I am not aware of to achieve this using systemd on Linux (Kernel 3.19)?
The service would be used to send a SIGNAL to a defined process. The Linux is running on an embedded system.
Thanks!
Because you use Systemd you might already use systemd-networkd for managing your devices instead of relying on 3rd party code.
You could use the structured journal output to get the last 2 ADDRESS field of the current BOOD_ID.(sadly, there is no notification mechanism for address changes in systemd-networkd):
→ sudo journalctl -F ADDRESS -u systemd-networkd -n 2
192.168.178.29
So, if there is only one line output, there was no address change.
There is an solution in other question of StackOverflow. Just here:
Detecting a change of IP address in Linux
I like this code, it's easy, you onli need a cron job with frecuency as you need (I made a little change):
#!/bin/bash
OLD_IP=`cat ip.txt`
NEW_IP=`/sbin/ifconfig | awk -F "[: ]+'{ print $4}'`
if [ $NEW_IP != OLD_IP ]; then
YOU_COMMAND <commands>
echo $NEW_IP > ip.txt
fi
exit 0
I am completely new to scripting and am having some trouble piecing this together from some other online resources.
What I want to do is run a bash script that will grep for a keyword domain in the /etc/hosts file on multiple servers. In the output file, I am looking for a list of the servers that contain this keyword but am not looking to make any changes. Simply looking for which machines have this value. Since there are a bunch of machines in question, listing the servers I am looking to search for won't work, but the machine I am doing this from does have SSH keys for all of the ones in question.
I have a listing of the servers I want to query in three files on the machine (one for each environment) I am going to run this script from.
Linux.prod.dat
Linux.qa.dat
Linux.dev.dat
Each file is simply a list of server names in the environment. For example..
server1
server2
server3
etc...
I am totally lost here and would appreciate any help.
Here is an example:
KEYWORD=foo
SERVERLIST=Linux.prod.dat
OUTPUTLIST=output.dat
for host in $(cat ${SERVERLIST}); do
if [[ -n "$(ssh ${host} grep '${KEYWORD}' /etc/hosts && echo Y)" ]]; then
echo ${host} >> ${OUTPUTLIST}
fi
done
Try GNU parallel
parallel --tag ssh {} grep -l "KEYWORD" /etc/hosts :::: Linux.prod.dat
parallel run command multiple times substituting{}with lines from Linux.prod.dat file.
--tag switch adds value from the Linux.prod.dat on the beginning of the file. So, the output of the command will look like:
server1 /etc/hosts
server5 /etc/hosts
server7 /etc/hosts
Where server1, server5, etc. will be names of the servers where /etc/hosts contains KEYWORD
i'm trying to figure out how to make a script for check if a dir exist in the network and than backup a directory in the network. Unfortunatly the IP of this machine (Windows 7 with samba) is not static and everytime is changing.
at the moment what I do for backup my notebook is:
in W7 notebook, launch cmq and with ipconfig check the ip of the machine
in linux, go in /etc/hosts file and change the IP set for the notebook
launch rsnapshot manually or wait for the crontab to do it
now what I want to do is a script that does:
to check which IP is available in a range of IPs
check which one has a specific dir available
if both tests are ok, I change the hosts name with the IP and I lanunch the rsnapshot.
maybe a smartest way could be to check if the MAC Address is available in the network and which IP is associated to it and launch the rssnapshot after have changed the hosts or the rsnapshots.conf file
till now what I did is:
for ip in 192.168.1.{128..142}; do # for loop and the {} operator
ping -c 1 -t 1 $ip > /dev/null 2> /dev/null # ping and discard output
if [ $? -eq 0 ]; then # check the exit code
if [check if dir exists for ip $ip] #not sure how do this check
/usr/bin/rsnapshot daily
else
echo "${ip} is down"
fi
done
Use smbclient to list (-L) the shares ex. :
smbclient -L SERVERNAME | grep -i "YOURSHARENAME"