Project rex


4.1  —  2022-03-17
* Hostgroup stack

Rex now maintains a stack of hostgroups.  Once you push a hostgroup
name on stack, that hostgroup will be used by any subsequent rex
command, unless it is given the -g option.  The new command "group"
(see below) provides ways to pop items off the stack, swap arbitrary
element with the top of stack, select new hostgroups on the fly, etc.

* New command: rex group

The "rex group" command has the following forms:

  rex group push GROUP
    Push GROUP on stack.

  rex group pop
    Pop the topmost group off the stack.

  rex group swap N
    Exchange top of the stack with the Nth element (0-based).

  rex group drop N
    Remove Nth element from the stack.

  rex group select COMMAND ARGS...
    Create on top of the stack a temporary group that contains
    those hosts from the current hostgroup where the supplied
    shell command returns success, i.e. exits with code 0.

  rex group show
    List the contents of the hostgroup stack.

* Add configuration function for overriding PTR records from rc files

Rex is a remote execution utility that runs a supplied command on a set of remote hosts. Arbitrary data can be supplied to the command in the form of local files, which will be transferred to each remote host prior to running the command and removed afterwards. Both parallel and sequential execution is supported.

Special mode exists to distribute a file or files to several hosts.

Rex is written in TCL and has extensive scripting facilities. It provides a convenient way to administrate multiple servers.

The program is designed to operate in a minimalistic environment. It is self-contained and does not need any external libraries.