What version is installed

1. openssh
sudo rpm -qa | grep -i openssh

2. mod_jk
telnet localhost
GET /x

2. Apache
httpd -v

3. MySQL
mysqadmin -u -p versioninfo

Add a startup script

/sbin/chkconfig --add sshd

Read about

Lucene
JMX
JDNI (?)

DTO - data transfer object

Hibernate -Bags

Find files created yesterday or before.

# create a file that has a timestamp of just after midnight today
touch -t `date +"%Y%m%d"0001.01` /tmp/just_after_midnight_today

# find files older than today
find /path/to/dir/ -maxdepth 1 ! -newer /tmp/just_after_midnight_today