[ale] Cron Management

[Lightner, Jeff]

It isn't just centralized scheduling.   It is the ability to schedules with dependencies so that discrete jobs have to run SUCCESSFULLY before others are kicked off.   

You can certainly write sophisticated scripts and setup crons that approximate this behavior but there's nothing like having a centralized tool where all each person has to worry about is the individual scripts/jobs and sets their own dependencies.

As I noted before we use cron but for a nightly Oracle backup we have to do the following steps:
1)  Stop test database that sits on previously synchronized and split mirror from Production DB.
2)  Unmount filesystems and export LVs on two separate servers separate from the Production server.
3)  Start disk (LUN) synchronization of the disks on each of those servers to the ones on the Production server.  (i.e. IBM BCV/SRDF or Hitachi Shadow Image mirroring).
4) Monitor the synchronization until it hits 100%
5) Stop Oracle Production DB or put it into hot backup mode.
6) Split the synchronized disks.
7) Restart the Production DB or take it out of hot backup mode.
8)  vgimport LVs and remount on the two servers.
9) Restart the test DB on one of the servers.
10) Start backup to tape or dedupe appliance from the other server.

We use multiple cron jobs and scripts in tandem with ssh to accomplish the above and it works quite well.   We even submit an "at" job to a similar setup to start the backup at a later point in the day.   However, doing all that would be much simpler if each of the scripts were actually "jobs" in a "scheduler".   We could make each job dependent on success of the previous one without having to include tests in successive jobs.   We could also eliminate the need for ssh and at calls on the other hosts as the scheduler would run the jobs on those hosts.   We could also pause the entire process at any point (or abandon it completely if time was running out) easily.   Without a scheduler we have to be sure to keep track of where we are in the set of scripts and or figure it out in the middle of the night if something goes wrong.

Jeffrey C. Lightner
Sr. UNIX/Linux Administrator
 
DS Services of America, Inc.
2300 Windy Ridge Pkwy
Suite 600 N
Atlanta, GA  30339-8461
 
P: 678-486-3516
C: 678-772-0018
F: 678-460-3603
E: jlightner at dsservices.com


-----Original Message-----
From: ale-bounces at ale.org [mailto:ale-bounces at ale.org] On Behalf Of Beddingfield, Allen
Sent: Tuesday, January 19, 2016 12:17 PM
To: Atlanta Linux Enthusiasts
Subject: Re: [ale] Cron Management

This is more about centralized management of cron, or some other centralized job scheduler. For example, one central console that controls jobs running on hundreds of machines... 

--
Allen Beddingfield
Systems Engineer
The University of Alabama

________________________________________
From: ale-bounces at ale.org [ale-bounces at ale.org] on behalf of Steve Litt [slitt at troubleshooters.com]
Sent: Tuesday, January 19, 2016 10:48 AM
To: ale at ale.org
Subject: Re: [ale] Cron Management

On Tue, 19 Jan 2016 10:52:06 -0500
Jerald Sheets <questy at gmail.com> wrote:

> Below.
>
> Jerald Sheets
> questy at gmail.com
>
>
>
> > On Jan 19, 2016, at 10:19 AM, DJ-Pfulio <djpfulio at jdpfu.com> wrote:
> >
> > For really complex needs, people use Ansible to manage puppet 
> > environments. ;)
>
> If you have to do this, you just don't Puppet good.  Completely 
> unnecessary, and we're partners of both companies.

What am I missing? Why not just use the same cron program we've been using for over 20 years? Write a few scripts, and it can do a heck of a lot of stuff.

SteveT

Steve Litt
January 2016 featured book: Twenty Eight Tales of Troubleshooting
http://www.troubleshooters.com/28



_______________________________________________
Ale mailing list
Ale at ale.org
http://mail.ale.org/mailman/listinfo/ale
See JOBS, ANNOUNCE and SCHOOLS lists at
http://mail.ale.org/mailman/listinfo

_______________________________________________
Ale mailing list
Ale at ale.org
http://mail.ale.org/mailman/listinfo/ale
See JOBS, ANNOUNCE and SCHOOLS lists at
http://mail.ale.org/mailman/listinfo