Automation - The Practice of Cloud System Administration - page 249

12.2.2 Example: Machine Configuration
In IT we are making a similar transformation. In a typical cloud computing environment,
every new machine must be configured for its role in the service. The manual process
might involve loading the operating system, installing certain packages, editing configur-
ation files, running commands, and starting services. A system administrator (SA) could
write a script that does these things. For each new machine, the SA runs the script and the
machineisconfigured.Thisisanimprovementoverthemanualprocess.Itisfasterandless
error prone, and the resulting machines will be more consistently configured. However, an
SAstillneedstorunthescript,sotheprocessofsettingupanewmachineisnotfullyauto-
mated.
Automated processes do not require system administrator action, or else they reduce
it to handling special cases. To continue our example, an automated solution means that
when a machine boots, it discovers its identity, configures itself, and becomes available to
provide service. The role for an SA who configures machines is eliminated in most cases.
TheSA'sroleistransformedintomaintainingtheautomationthatconfiguresmachinesand
handling unusual hardware or operating systems.
12.2.3 Example: Account Creation
Cloud administrators often maintain the systems that make up a service delivery platform.
To give each new developer access, an SA might have to create accounts on several sys-
tems. The SA can create the accounts manually, but it would save a lot of time if the SA
wrote a script that creates the accounts on all the relevant machines, and there would be
lesschanceofskippingastep.Eachtimeanewdeveloperjoinsthecompany,theSAwould
use this account creation tool.
Better yet would be if the SA wrote a job that runs periodically to check if new deve-
lopers are listed in the human resources database and then automatically create the new
accounts. In this case, the SA no longer creates accounts; the human resources department
does. The SA's job is maintaining and enhancing the account creation automation.
12.2.4 Tools Are Good, But Automation Is Better
Much of operational work consists of repeated tasks, such as configuring machines, cre-
ating accounts, building software packages, testing new releases, deploying new releases,
increasing capacity, failing over services, moving services, and moving or reducing capa-
city. All of these tasks can be improved with better tools, and these tools are often stepping
stones to automation.
Another advantage of automation is that it enables the collection of statistics about de-
fects or, in IT terms, failures. If certain situations tend to make the automation fail, those