Prevent DoS/DDoS On Linux

Posted on January 22, 2009 by wallace

Last month my server have been ddos by someone, so that I have search on the internet and see how can I prevent it. It’s juz very simple, as u know the linux firewall “iptable”. u can wirte a shell script monitoring the netstats and check whether an IP address have how many connections in this peroid. If there are more than X(u can set a variable on it) connections, the ip address will be ban for X minutes by iptables. Moreover, if there is any ip address has been banned, a email will sent to your administrator account, and I have tested by myself, it works! That’s a great shell script!

Checking how many connections does those IP address

If there are someone been banned, an email will be received

Testing the function:P 123.203.109.188 is my IP address and trying to hack DrKn(Kenny)’s Server 😛

backup your MySQL using a bash script and cron job

Posted on December 6, 2008 by wallace

From allenkan.com/blog
useful sql backup command
1. dump the DB into a sql file mysqldump -u <username> -p<password> <database> > <output file name>.sql


2. compress it

gzip <Filename>
3. Ftp send to backup server

** it is not suggested because backup ftp account and the backup data is sent in plain text format **
ftp -n $ftpserver <<END_SCRIPT

quote USER $ftpuser

quote PASS $ftppwd

put $gzipOutFile

quit

END_SCRIPT

exit 0

２４／１０

Posted on October 24, 2008 by wallace

All STEAM server needs to be update since yesterday, otherwise the server will be pop-up a warning message something like…”Please update and restart the server”. If you ignore this warning, your server will not be listed on the master server list.

The new version was 4381 for windows and for linux it was 4352. It has also changed the protocol from 47 to 48. Therefore, the old version client can not connect to the new server anymore unless you update the new version. It means that the old version of non-steam client could not getting into the new version server. The new version of client can not join the server which hasn’t been upgraded as well.

Those servers which are hosted by wallaceho.com has been prompt upgraded to new version. However, there are still have many server which have not been upgraded till to now, for example: hkspirit

The new version of client has added many functions, one of it is while you showing up the score board, you may saw the photo of your friend list.