For UNIX systems, OSSEC only requires gnu make, gcc, and libc. OpenSSL is a suggested, but optional, prerequisite. However, you always have the option to pre-compile it on one system and move the binaries to the final box.
On Ubuntu you will need the build-essential package in order to compile and install OSSEC.
To install the package run the following command.
OSSEC# apt-get install build-essential
If database support is needed mysql-dev or postgresql-dev should be installed. Run the following command to install these packages.
# apt-get install mysql-dev postgresql-dev
To use the SQLite features, the libsqlite3-dev package is necessary.
New in version 3.0.
# apt-get install libsqlite3-dev
RedHat should have all packages needed by default, but if database support is needed the package mysql-devel and/or postgresql-devel will need to be installed.
# yum install mysql-devel postgresql-devel
To use the SQLite features, the sqlite-devel package is necessary.
New in version 3.0.
# yum install sqlite-devel
Debian has replaced bash with dash, and this may cause issues during installation. Dash does not appear to support all of the features available in other shells, and may display an error when trying to set the server’s IP address on an agent system. The error can be ignored, but the server ip address will need to be set.
Do this by making sure something like the following information is in the agent’s ossec.conf:
<ossec_config>
<client>
<server-ip>SERVER'S IP</server-ip>
</client>
This can also be avoided by using bash to run install.sh:
# bash ./install.sh