On Sat, Nov 26, 2022 at 07:07:54AM -0700, Charles Curley wrote: > On Sat, 26 Nov 2022 06:40:24 -0500 > Amn Ojee Uw <amnoje...@gmail.com> wrote: > > > If from the command prompt or a shell script, I run this code sudo > > '/opt/tomcat/bin/catalina.sh run', Tomcat runs nicely, but it grabs > > the Terminal, if I close the Terminal, Tomcat just stops working. > > Obviously not a perfect solution. > > The solution to that is to put the Tomcat instance into the background > by appending an ampersand to the command, like so: > > /opt/tomcat/bin/catalina.sh run & > > In Windows, the ampersand is unnecessary; programs go into the > background according to the type of program they are. In Unix, one must > specify.
I wish. No, it's the same in Unix. Some programs have been written to self-background. It was a big thing back in the 1990s. It's horrible design, and it makes writing init script (or their equivalent) so much more difficult. What's you've said here is correct from the point of view of someone starting the service manually in a shell, without a supervisor. But it doesn't address the issue of how to write an systemd unit to run this thing correctly. I'm not a tomcat user myself, so I can't really give much advice on writing a unit file for it. All I can give are general tips. If you HAVE to run a shell script (I'm assuming "catalina.sh" is a shell script) to start this service, then you're probably not going to be able to write a normal systemd unit that manages a single process. You're stuck writing one that manages a FLEET of processes, because that's what shell scripts do. They create multiple processes, either ephemeral ones, or persistent ones, or both. The good news is that systemd was written with the knowledge that such things still exist in the world, and that a unit file might have to deal with them. In systemd.service(5) you'll find a description of the basic types of services that can be started. The one you want is called "forking". Type=forking You'll need to read and understand the systemd documentation *and* the tomcat documentation, and find a combination of the two that can coexist. This may mean researching this catalina.sh script and looking for options to make it do what systemd expects. More likely it will mean finding a tomcat support mailing list, and asking the people *there* how they made it start. I'd be shocked if there isn't already someone out there with a functioning systemd unit file to start your version of tomcat properly.
