The first stage, the workshop stage, that is, all the operation and maintenance problems we encountered were basically completed by manual operation. In this case, the scale of the system is not large, and the problems encountered are relatively simple, mostly concentrated on the hardware, network and system level, so people with certain operating system or network maintenance experience can solve them.
The operation and maintenance in this scenario, that is, SA, the system administrator, usually has multiple roles, and the number is not too large.
The second stage, the scripting tool stage, generally most enterprises will quickly transition from the first stage to the second stage, because a large number of repetitive and cumbersome operations in the previous stage can be completely converted into scripts, instead of typing a bunch of similar commands every time.
Early SAs were mainly based on various shells, so many SAs would be very competitive if they could write some batch scripts in the shell. Later, we all know that Perl, Ruby, Python and other dynamic languages are also widely used in the realization of scripting tools, especially in the automatic realization of some relatively complex logic and scenarios.
Three stages, process and tool stage, when we package some complex operations into scripts, the efficiency will indeed improve a lot, but the business scenarios and volumes we face are becoming more and more complicated. For example, for operation and maintenance students, they used to be responsible for installing and configuring the operating system. If it is dozens or hundreds of sets, the scripts can be executed in batches.
But in the future, the operation and maintenance department will be responsible for the frequent release of software, many times a week or even every day, which is determined by the business characteristics, especially the Internet-type business, which is completely different from the traditional monthly or even monthly release scenario. Moreover, with the increase of users, the number of servers may have reached hundreds of thousands, and the deployed services are not the same. It is completely impossible to meet the requirements simply by script execution.
At this time, we need to face more complicated scenarios, such as making a business deployment. Operation and maintenance students may need to install servers, modify system configuration, install software packages, start and stop processes, and then load balance the configuration services. At this time, a process is needed to connect the script functions in series, and at the same time, some processes check and judge the script execution results.