index.txt (2958B)
1 SYSMGR 2 ================================================================================ 3 4 sysmgr is a service manager that aims to do as little as possible for service 5 supervision. It can be viewed as a simplified version of [runit]. It only cares 6 about making sure certain processes are alive unless explicitly stopped. Unlike 7 runit, it doesn't care about logging, or stopping daemons with special commands, 8 as those can easily be handled by service scripts themselves. It doesn't have 9 supervise directories with FIFOs inside. It _ONLY_ cares about processes and 10 nothing else. 11 12 [runit]: http://smarden.org/runit 13 14 15 Interacting with sysmgr 16 -------------------------------------------------------------------------------- 17 18 While sysmgr can be interacted entirely with POSIX base tools, sysmgr provides 19 a tool named 'svctl' for interacting with sysmgr. This tool can be used to check 20 the status and start/stop/restart services. 21 22 When sysmgr picks up a service script inside the service directory, it 23 automatically starts the service unless stopped. 24 25 26 Details of implementation 27 -------------------------------------------------------------------------------- 28 29 The initial implementation of sysmgr was written in POSIX shell, and it used 30 POSIX compliant base-tools, however, in order to spawn as little processes as 31 possible, it did some Linuxisms which prevented portability. The current 32 implementation is written in C99, and it only uses functions from the POSIX-2008 33 C Library, so it should work on all POSIX-compatible systems. Testing required. 34 35 36 Building and installing 37 -------------------------------------------------------------------------------- 38 39 Before building sysmgr, it is best to take a look at the config.h and config.mk 40 files, and modify them to fit your system. Afterwards you can do the following 41 (as root if necessary): 42 43 make 44 make install 45 46 47 You can then install service scripts to your service directory and run sysmgr. 48 49 50 Service scripts 51 -------------------------------------------------------------------------------- 52 53 Service scripts can be any executable ranging from shell scripts to C binaries. 54 The only requirement is that they can be executable. An example script is as 55 follows: 56 57 #!/bin/sh -e 58 exec httpd -f -p 8080 -h /var/pub/www 59 60 61 The exec call in the shell script makes sure that sysmgr is tracking the process 62 id of the httpd program rather than the shell script. It isn't necessary, but it 63 is the best practice to do so. 64 65 On certain occasions a service can depend on other services to be able to start. 66 That's why a sysmgr-depends tool is supplied, in order to make sure a service 67 can wait until another service is up. 68 69 #!/bin/sh -e 70 sysmgr-depends dbus 71 exec NetworkManager -n 72 73 74 More information 75 -------------------------------------------------------------------------------- 76 77 More usage information can be found on the following manual pages: 78 79 - runsyssv(1) 80 - svctl(1) 81 - sysmgr(8) 82 - sysmgr-depends(1) 83