Introduction
Portage is an amazingly simple and complex piece of technology. The simplicity in each piece’s ability to do a specific function comes together in a complex package management system that rivals all other forms of package management (at least in my opinion). Automating updates is something that admins everywhere do out of necessity. Heck, automating everything is an admin’s life. Automating portage’s updates is a bit more harrowing than other package management systems but it isn’t impossible.
Problem
As admins we attempt to simplify the work we actually do by writing scripts and programs to do most of our job for us. It’s often been said that systems admins are the only people whose job description is to remove their job responsibilities.
Portage doesn’t have any default automation for doing nightly or even weekly portage updates but that doesn’t stop the creative from coming up with their own solution. A simple but elegant solution is to create a small cron script that runs every day. The problem comes when you want to read the wonderful output of portage (sometimes these messages can guide you when problems are about to occur) to avert disasters. If the updates are performed from cron, the output will be preserved in an e-mail to the appropriate user but then we have to sift through all of the output at once. This also doesn’t solve the issue if the updates are performed by another utility such as puppet. These annoying little changes to the problem require a slightly more elegant solution.
Solution
The solution is to take advantage of portage’s logging specifications. From the make.conf man file:
- PORTAGE_ELOG_CLASSES
- PORTAGE_ELOG_SYSTEM
- PORTAGE_ELOG_COMMAND
- PORTAGE_ELOG_MAILURI
- PORTAGE_ELOG_MAILFROM
- PORTAGE_ELOG_MAILSUBJECT
Using a combination of these directives in the make.conf file allows us to log the reports from portage to a large number of locations. If we wanted to simply add mailing output (not the full build output just the messages) we would add the following directives to make.conf:
PORTAGE_ELOG_SYSTEM="save mail" PORTAGE_ELOG_MAILFROM="portage@alunduil.com"
This simply adds the mailing log utility to portage and specifies that the e-mails come from the address portage@alunduil.com. Of course, much more complex configurations can be crafted to suit any admins’ needs.
Conclusion
Letting your servers notify you of possible actions is one way of automating maintenance tasks; making maintenance eventually disappear from your task list. By starting with the tasks that are repeated the most frequently, you can quickly free up time for higher level automation and organization which leads to a cleaner and sturdier infrastructure.