Time Management for System Administrators

Copied the QA site to the live site.

Marketing demanded a way to make emergency updates when the QA department wasn't available. We created this command:

emergency-draft-to-live

Copied the draft site directly to the live site after asking 'Are you sure?' a few times.

These three scripts comprised Layer 2, which I mentioned earlier. Layer 1 was a script that did the actual copying of one site's data to another site, making a backup along the way, and setting files to read-only (changing the ownership of the files, too). Layer 1 had to be done as root because it was changing ownership of files and accessing machines via secured channels.

sudo was programmed as described in Table 13-1.

Table 13-1. Web update permission table

Web developers

QA

Marketing

Readyforqa

X

X

Golive

X

Emergency-draft-to-live

X

We actually went through the effort of having management sign off on this chart, with real signatures, to make sure they understood that they were agreeing to what they thought they were agreeing to. The political process to get this approved was the difficult part. It took weeks. Presenting the information to management in the chart form made it a lot easier for a decision to be made. They could understand and update the chart themselves until they were happy with it. Translating the final chart into a sudo configuration file was the easy part.

Per Layer 3, we decided to make an easier way for people to access these commands. We considered a web interface, but, in this case, the users were satisfied with a menu program that presented them with a list of options that ran the appropriate command.

The menu ran without any additional privileges (i.e., not under sudo), but called the Layer 2 programs using sudo as needed .

Summary

Automation is great because it saves you time. It also permits you to push work to other, less-technical people.

There are four types of problems that SAs typically deal with:

Simple things done once

Hard things done once

Simple things done often

Hard things done often

'Hard things done once' and 'Simple things done often' are the right things to try to automate. 'Hard things done often,' while tempting, is usually better served by off-the-shelf packages (commercial or free).

To automate a process, first be sure you can do the steps manually. Then document each step, and make sure that you can automate each step. Then bring all of the steps together.

You can save a lot of typing time by making aliases. This is true for command-line systems as well as for applications, such as SSH. Set the alias as close to the actual application as possible. For example, setting the alias in the SSH configuration file means all systems that leverage SSH will use the alias.

The Unix/Linux make command is extremely powerful. It is not just for programmers. You can use it to automate system administration tasks. On Unix/Linux systems, especially servers, standardize on having a Makefile in /etc that automates common tasks such as reindexing aliases, cloning data, and so on.

Bash and /bin/sh shell languages are more sophisticated and powerful than you may realize. The examples in