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My static IP was on Verizon's network, who are subletting their Fios lines to Frontier. Now I am given a new static IP from Frontier's data network. May I have a ballpark list of configurations to change to the new IP? It is like me to miss one thing and cause a problem. I have a LAMP with proftpd & ssh tunneling.

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  • Firewall: if you've put a firewall rule in which denies all traffic which where not designated for your IP, you need to change that.
  • Interfaces file: Change the static IP in /etc/network/interfaces. This file is re-read when the network connection is set up again.
  • ProFTPd: the address on which ProFTPd is listening on
  • Apache: the address on which Apache is listening on. Also check your virtual host settings like <VirtualHost> and NameVirtualHost
  • MySQL: check the address it's listening on. Usually, this is set to listen on all addresses.
  • DNS: all records which point to your IP.
  • To make sure you did not forget anything, search all files on your server for the old IP address using:

    sudo grep -HrnF '' /

    This command shows every occurence of the IP address as filename:line: line with

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Thank you, this is what I was looking for. I ran the grep command but ran into this: sudo@server:~$ sudo grep -HrnF '' / grep: /usr/share/doc/bash/completion-contrib: No such file or directory grep: /usr/share/doc/libsane/supported.html: No such file or directory grep: /usr/share/man/man5/modprobe.d.5: No such file or directory grep: warning: /usr/bin/X11: recursive directory loop grep: /usr/src/linux-headers-2.6.32-28-server/source: No such file or directory And the process did not return me to command prompt. Is it safe to assume that my files were searched through? – aesthetic priest Apr 15 '11 at 21:49
@aesthetic priest: When the process has completed, the program will return to shell. If you want to quit the search, press Ctrl + C. Note that this script searches for a literal occurence of Other forms like 1. 23.234. 5, or array(1,2,3,4) are not included. Use it as a tool to find references you've forgotten about. – Lekensteyn Apr 16 '11 at 8:14
Maybe we should add I and --devices=skip to the grep command otherwise it will hang (don't know the exact reason, but it seems read somewhere in /proc). Next, redirect output to a file > oldips.txt, otherwise output may be lost (e.g. if it finds an old mailbox file with lots of old IP addresses). – Thomas Weller Mar 24 '14 at 22:44
It's probably a better idea not to start searching in /, but look in /usr /etc /home /srv /var /boot /opt (and any additional custom dirs such as /media /mnt /www /your-own-dir). Descending in /proc /sys /dev is not sensible indeed. – Lekensteyn Mar 24 '14 at 23:12

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