Linux Ask! is a Q & A web site specific for Linux related questions. Questions are collected, answered and audited by experienced Linux users.
How to convert ext2 partition to ext3?
Answer:
Firstly, you need to create a journal on it. This can be done either the file system is mounted or unmounted.
# tune2fs -j /dev/hdaX
Then, mount the filesystem as ext3
# mount -t ext3 /dev/hdaX /mnt/somewhere
Reference: http://batleth.sapienti-sat.org/projects/FAQs/ext3-faq.html
Packet sniffing with tcpdump
Answer:
To perform packet sniffing, it is easy with tcpdump
# tcpdump -i eth0 -w dump.cap -s 0After you terminated the tcpdump, you can use tool such as Wireshark to analyse the dump.cap.
Find out which programs are listening TCP port
Answer:
Use the command: netstat -tlnp
# netstat -tlnp
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:25 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:443 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN
How to unset an environment variable in bash
Answer:
To unset an environment variable in bash, you can use the unset command.
Example:
# export foo=bar
# echo $foo
bar
# unset foo
# echo $foo
Install Xdebug for PHP under Ubuntu
Answer:
Xdebug is a very useful debugging extension for PHP, to install under Ubuntu:
# sudo pecl install xdebug
# echo "extension=xdebug.so" > /etc/php.d/xdebug.ini
Restart Apache and that's all.
