Re: [Condor-users] Condor pool = Windows + Linux ?

[Ian Chesal <ichesal@xxxxxxxxxxxxxxxxxx>]

On Wed, Oct 20, 2010 at 8:22 AM, Sónia Liléo <sonia.lileo@xxxxx> wrote:

I have been using a condor pool with 4 Windows machines that has been working without problems.

 

I am now trying to configure a new condor pool composed by a central manager that runs Windows and an execute machine that runs Linux.

 

I am running the Condor daemons in the Linux machine as root.

 

The software that invokes Condor requires that the submitted jobs have access to a shared directory that exists on the central manager/submitting machine.

I have therefore set up a dedicated account on the execute machine in order to run the jobs.

The execute machine has 4 cores. I have therefore defined SLOT1-4 on the following way,

 

SLOT1_USER = tachi-02\root

SLOT2_USER = tachi-02\root

SLOT3_USER = tachi-02\root

SLOT4_USER = tachi-02\root

DEDICATED_EXECUTE_ACCOUNT_REGEXP = True

This sort of dedicated account stuff doesn't apply to Linux. It's Windows only.

The jobs will run on the Linux nodes as the user who submitted them. You need to make sure that user is the user db on every Linux node in your pool. See 'man useradd' on your Linux machine for details on how to add a user. It's usually enough to just add the user name. So if your Windows Domain account is MYDOMAIN\myuser you can add a 'myuser' to your Linux nodes.

 

 I have then tried to store the password for this account on the execute machine

 

root@tachi-02:~# condor_store_cred add

Account: root@(null)

 

Enter password:

 

Operation failed.

    Make sure your ALLOW_WRITE setting includes this host.

 

This operation worked fine on my previous Windows condor pool as long as I had the condor_schedd running when storing the password.

Password storage is a Windows-only thing. Condor doesn't need your user's password when it's running on Linux as long as the daemons are started as root. They can switch user context to any other user without needing that user's password.

 

1.       Why doesn’t it work on the Linux machine? The condor_schedd daemon is running and the variable ALLOW_WRITE is set to *.

2.       Does condor_store_cred add works on a different way on Linux as compared to Windows?

It doesn't work at all on Linux. It's not needed. See above. 

3.       How should I store the password on a Linux machine?

Add all the users who will be running jobs to the machine using useradd. Optionally you can set up a centralized user authorization system for your Linux machine like LDAP or NIS or use Samba to authenticate against your Windows Domain controller. But all of this very much outside of the scope of Condor -- this is Linux admin stuff.

 

I have another question.

 

I have tried to set the variable DAEMON_LIST in the condor_config file of the execute machine as shown below.

##  Daemons you want the master to keep running for you:

DAEMON_LIST                     = MASTER, STARTD

 

However, the variable does not seem to change even after rebooting the system.

root@tachi-02:~# condor_config_val DAEMON_LIST

COLLECTOR, MASTER, NEGOTIATOR, SCHEDD, STARTD

 

Why doesn’t this variable change?

Ask Condor what file it's getting the setting from. Likely you've got the value set in the condor_config.local file. You can ask it with:

condor_config_val -v DAEMON_LIST

And it'll tell you where DAEMON_LIST was defined at.

Regards,

- Ian