I enabled UFW on an Ubuntu server recently and started getting all manner of stuff in my logwatch reports. It activated a section called 'iptables' and started logging every line in syslog with [UFW BLOCK] in it. It was marginally interesting, but not really worth the space devoted to it, so I decided to write a little script to parse the UFW log and summarise the top Blocked Hosts and top Blocked Ports. Therefore I could easily see if there was a change in pattern.
Linux
Power Mutt usage.
I always install mutt when I'm setting up a server, mainly because I use it to send myself files from the command line, for local examination or archiving. Its quicker than using scp, ssh, or (heaven forbid) ftp. Plus you can use it in shell scripts. For example; But recently I was troubleshooting a server … Read more
Dos Boot Disks Under Linux
Sometimes you have no choice and you need to boot into a DOS boot disk — to upgrade your BIOS for example, or to run Seagate's SeaTools, as I had to recently. This can be a headache when you're using Linux. I was having issues with the SeaTools' own boot disk, as I wanted to … Read more
Viewing heavily commented config files
Just a quick one, as I haven't posted for a while. This is a cool trick for getting the juice out of heavily commented files. In particular I used this on /etc/samba/smb.conf, but also good for apache2.conf, php.ini etc. The magic is this. grep -v -e "^#" -e "^;" -e "^$" /etc/samba/smb.conf Basically, ignore all … Read more
Joomla and mysterious memory usage
I've been running a server which has a fairly busy Joomla site on it. The server has 2Gb RAM, and is running nginx, php5-fpm and mysql, and not much else. However it would run for a while and then the disk would start swapping out. Not a lot, but enough to cause a few issues. If I restarted the server, memory usage would start at something like this
>$ free total used free Mem: 2048036 1024048 1023988 Swap: 4192960 0 4192960
After about a day it would look like this
>$ free total used free Mem: 2048036 1924048 73988 Swap: 4192960 0 4192960
And eventually it would have a flurry of activity which would make it look like this
>$ free total used free Mem: 2048036 1924048 23988 Swap: 4192960 4567 4188393