I use it everyday and what it basically does is gives the end user to run multiple scripts in detached mode (background), however a user can log in to the Detached Session whenever s/he wants at any given time. Only the data owner can know what's right for them.You could use a very nice tool called tmux. But in a banking system, it's a disaster of epic proportions. But what good is great performance if you lose data? On SOME applications, like, say, Netflix streaming video recording at what point you're viewing, absolute fidelity may not be particularly important - maybe, even, your customers LIKE the video backing up a bit following a failure. Formerly, they have paid less attention to these aspects and more attention to performance. As a person who has specialized in database systems for over 26 years, I can tell you that it's only been in very recent times that MySql has started to get its act together regarding competency at the most important facets of what database systems are for - data security / integrity. ![]() The ONLY way you can really address this is replace MySql (PostgreSql is a great replacement) OR write your own shutdown script that FIRST coddles MySql like a baby, and when it's happy to be shut down THEN shuts down the system. The problem here is NOT your method of shutdown, is the piece of software that can't handle a shutdown properly MySql. However, sometimes that causes MySQL issues. I have a feeling you may not like this answer, but THIS answer includes some insight none of the others consider. Similar issues can be found with systems using huge buffers and sparse I/O availability. I once had a MySQL instance with +300.000 tables that took over an hour to exit. Often this is due to the massive load of work that needs to be done before the daemon can be exited safely. You will be better off fixing the root-cause of your worries: MySQL not shutting down properly. One exception is using the reboot command with the -f option, this will skip executing init scripts and will reboot the system directly. This will clean up the rest before an ACPI call is done to really reboot or shutdown your system. At the end, when all init scripts are executed, the inevitable will happen: all processes still running will get a SIGTERM signal and, after a few seconds (2 or 5), a SIGKILL. The shutdown process will continue as if nothing was wrong, only taking a bit longer and probably print a warning. When the stop argument is given and the daemon will not be shutdown in a fair amount of time, the script will stop and exit giving a failure. Individual init scripts can have a timeout, like the MySQL init script in CentOS. Shutting down using init scripts step by step stop all your services registered under usually runlevel 'S'. Basically they all initiate the shutdown run-time of your SysV (CentOS =7) scripts (I will call them init scripts for ease of reading). Modern distributions will have all tasks covered regardless of the command you are using. Most init scripts call halt to make a log in utmp.New versions of reboot (>2.74) will initiate shutdown if not in runlevel 0 or 6. ![]() reboot is a wrapper round shutdown which does some harddisk maintenance (syncing and/or putting in standby mode and not really relevant).Adding the argument -r and a specific time (or ' now') will reboot your system instead of halting it after the shutdown sequence. shutdown is the most common way to stop your system.For the difference between the commands see the manpage for systemctl ( man systemctl) for it is quite nicely documented.įor CentOS 6, there is no better way to restart your server by using anything else than any those commands stated in the original question: The systemctl program will detect the use of the symlink and run the systemctl command with the correstponing arguments. ![]() Systems using systemd (CentOS >=7) will have the reboot, shutdown and halt commands symlinked to systemctl to handle the reboot.
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