Rex is about Running Tasks

Rexfile defines tasks

desc 'Check the disk free on the relevant drives';
task 'df' => sub {
    say scalar run 'df -H /usr*';
};

rex runs tasks

$ rex df
[2015-04-08 12:17:39] INFO - Running task df on <local>
Filesystem             Size   Used  Avail Use% Mounted on
/dev/mapper/VGRoot-LogVolroot
                       5.3G   3.5G   1.6G  70% /
/dev/sde1               64G    41G    20G  68% /usr2

Rex runs tasks on hosts

rex -H <host> <task>

$ rex -H scsqhdadap01 df
[2015-04-08 12:18:54] INFO - Running task df on scsqhdadap01
[2015-04-08 12:18:54] INFO - Connecting to scsqhdadap01:22 (nbkyslo)
[2015-04-08 12:18:54] INFO - Connected to scsqhdadap01, trying to authenticate.
[2015-04-08 12:18:54] INFO - Successfully authenticated on scsqhdadap01.
Filesystem             Size   Used  Avail Use% Mounted on
/dev/mapper/volgrp01-root
                       8.4G   4.1G   3.9G  52% /
/dev/mapper/volgrp02-usr2
                       144G    65G    73G  47% /usr2
/dev/mapper/volgrp01-usr3
                       108G    73G    30G  72% /usr3
/dev/mapper/volgrp03-usr4
                       432G   203G   208G  50% /usr4
/dev/fioa              773G   419G   315G  58% /usr5

$ rex -H 'scsqhdapap[01..04]' df

Rex deploys files

task deploy_www =>
    sub {
        file '/etc/apache2/httpd.conf',
            ensure => 'present',
            source => 'etc/httpd.conf',
            ;
    };

Rex runs callbacks when deploying

task deploy_www =>
    sub {
        file '/etc/apache2/httpd.conf',
            ensure => 'present',
            source => 'etc/httpd.conf',
            on_change => sub {
                run 'apachectl restart';
            };
    };

Rex can generate files from templates

task deploy_www =>
    sub {
        my $config = template(
            'etc/httpd.conf',
            server => connection->server,
        );

        file '/etc/apache2/httpd.conf',
            ensure => 'present',
            content => $config,
            on_change => sub {
                run 'apachectl restart';
            };
    };

Rexfile configures host groups

group ops_prd => 'scsqhdapap0[1..4]';
group ops_uat => 'ltwqhdacap0[1..4]';
group ops_dev => 'scsqhdadap0[1..2]';

Rex runs tasks on host groups

rex -g <group> <task>

$ rex -g ops_dev df
[2015-04-08 12:23:21] INFO - Running task df on scsqhdadap01
[2015-04-08 12:23:21] INFO - Connecting to scsqhdadap01:22 (nbkyslo)
[2015-04-08 12:23:21] INFO - Connected to scsqhdadap01, trying to authenticate.
[2015-04-08 12:23:22] INFO - Successfully authenticated on scsqhdadap01.
Filesystem             Size   Used  Avail Use% Mounted on
/dev/mapper/volgrp01-root
                       8.4G   4.1G   3.9G  52% /
/dev/mapper/volgrp02-usr2
                       144G    65G    73G  47% /usr2
/dev/mapper/volgrp01-usr3
                       108G    73G    30G  72% /usr3
/dev/mapper/volgrp03-usr4
                       432G   203G   208G  50% /usr4
/dev/fioa              773G   419G   315G  58% /usr5
[2015-04-08 12:23:25] INFO - Running task df on scsqhdadap02
[2015-04-08 12:23:25] INFO - Connecting to scsqhdadap02:22 (nbkyslo)
[2015-04-08 12:23:27] INFO - Connected to scsqhdadap02, trying to authenticate.
[2015-04-08 12:23:30] INFO - Successfully authenticated on scsqhdadap02.
Filesystem             Size   Used  Avail Use% Mounted on
/dev/mapper/volgrp01-root
                       8.4G   1.8G   6.2G  23% /
/dev/mapper/volgrp02-usr2
                       144G    95G    42G  70% /usr2
/dev/mapper/volgrp01-usr3
                       108G    90G    13G  88% /usr3
/dev/mapper/volgrp03-usr4
                       432G   258G   153G  63% /usr4

Rexfile configures environments

environment ops_dev => sub {
    group all => 'scsqhdadap0[1..2]';
    group reuters => 'scsqhdadap02';
    group db => 'scsqhdadap02';
};

environment ops_prd => sub {
    group all => 'scsqhdapap0[1..4]';
    group reuters => 'scsqhdapap04';
    group db => 'scsqhdapap01';
};

Rex runs tasks in environments

rex -E <env> <task>

$ rex -E ops_dev -g db df
[2015-04-08 12:35:31] INFO - Running task df on scsqhdadap02
[2015-04-08 12:35:31] INFO - Connecting to scsqhdadap02:22 (nbkyslo)
[2015-04-08 12:35:32] INFO - Connected to scsqhdadap02, trying to authenticate.
[2015-04-08 12:35:35] INFO - Successfully authenticated on scsqhdadap02.
Filesystem             Size   Used  Avail Use% Mounted on
/dev/mapper/volgrp01-root
                       8.4G   1.8G   6.2G  23% /
/dev/mapper/volgrp02-usr2
                       144G    95G    42G  70% /usr2
/dev/mapper/volgrp01-usr3
                       108G    90G    13G  88% /usr3
/dev/mapper/volgrp03-usr4
                       432G   257G   153G  63% /usr4

Rexfile has configuration

set datlib => '/datlib/hist';
environment ops_uat => sub {
    set datlib => '/datlib/app1_dr';
};

desc 'Restart process controller';
task 'restart_pc' => sub {
    my $datlib = get 'datlib';
    my $env = environment;
    run "$datlib/pc/envs/$env/manager/bin/apache restart";
    run "$datlib/pc/envs/$env/manager/bin/boss.pl restart";
};

$ rex -E ops_dev -g pc restart_pc

Tasks can run other tasks

desc "Update the PC repository";
task 'update_pc',
    group => [qw( pc )],
    sub {
        my $datlib = get 'datlib';
        run "cd $datlib/pc/versions/master && git pull";
        die "Task failed. Stopping." if $?;
        run_task 'restart_pc', on => connection->server;
    };

$ rex -E ops_dev update_pc

Tasks can use parameters

desc "Install CPAN modules";
task 'cpan', sub {
    my ( $opt ) = @_;
    my $modules = join " ", split /[, ]/, $opt->{module};
    run "cpan $modules";
};

$ rex -g ops_dev cpan --module='Mojolicious Dancer'

Rex can sync directories

rsync

use Rex::Commands::Rsync;

task sync_www =>
    sub {
        sync 'www', '/var/www';
    };

Rex has more configuration

Rex::CMDB

Configure by host

Configure by environment

Configure by OS