Command Syntax using isi_for_array (tar, and $HOSTNAME)

No! spot the difference!

Peter

This is exactly why I gave the examples, to show how easily one can get it wrong.

And you have seen already how to do it correctly, use the single quotes (first example)

isilon-c702-1# isi_for_array 'echo $(hostname)'

isilon-c702-2: isilon-c702-2

isilon-c702-3: isilon-c702-3

isilon-c702-1: isilon-c702-1

isilon-c702-1# isi_for_array "echo $(hostname)"

isilon-c702-3: isilon-c702-1             <===  same filename

isilon-c702-2: isilon-c702-1             <===  same filename

isilon-c702-1: isilon-c702-1             <===  same filename   

isilon-c702-1# isi_for_array echo $(hostname)

isilon-c702-2: isilon-c702-1             <===  same filename

isilon-c702-3: isilon-c702-1             <===  same filename

isilon-c702-1: isilon-c702-1             <===  same filename

Ahh Haa!  your right!

You have to do something like this:

isi_for_array 'tar czf /ifs/`hostname`-crash.tgz /var/crash'

or you'll overwrite your tar file.  So be careful...

Try out these commands to see how tricky things can get with  isi_for_array

# isi_for_array 'echo $(hostname)'

# isi_for_array "echo $(hostname)"

# isi_for_array echo $(hostname)

Note: Only one of these will suit your needs, and please try to understand the underpinnings before proceeding your backup efforts.

And please try to anticipate what happens to your cluster when /usr and /var get accidentally overwritten by a misdirected tar extraction...

Take good care

-- Peter

Peter,

all worked!

isilon-c702-1# isi_for_array 'echo $(hostname)'

isilon-c702-2: isilon-c702-2

isilon-c702-3: isilon-c702-3

isilon-c702-1: isilon-c702-1

isilon-c702-1# isi_for_array "echo $(hostname)"

isilon-c702-3: isilon-c702-1

isilon-c702-2: isilon-c702-1

isilon-c702-1: isilon-c702-1

isilon-c702-1# isi_for_array echo $(hostname)

isilon-c702-2: isilon-c702-1

isilon-c702-3: isilon-c702-1

isilon-c702-1: isilon-c702-1

Your the man!  Thank you!

Peter,

Ok I ran the following command:

isi_for_array "tar -cvjf /ifs/css-backups/c702/$(hostname)_usr-backup.tar.bz2 /usr/"

Big mistake!  Lucky this is just a test vm cluster.  It put everything in the same .tar.bz2 file.  I need there to be a individual .tar.bz2 for each node.  Any suggestions?

Yes I saw this, but having a hard time translating that into the isi_for_array command:

isi_for_array 'tar -cvjf /ifs/css-backups/c702/'$(hostname)'_usr-backup.tar.bz2 /usr/'  (Does not work, it still overwrites)

A key thing to remember is that isi_for_array is just another command executed in a shell, and thus subject to all the character  manipulation that whatever shell you run it in has, in whatever node is executing it. 

Have fun with your virtual Isilon!

LOL, Brilliant... yes that is me .  Again, I am not so bright with the scripting, so thank you for baring with me .

I found this to work as well:

isi_for_array 'tar -cvjf /ifs/css-backups/c702/"$(hostname)"_usr-backup.tar.bz2 /usr/'

I am getting the hang of it a little bit

Thank you again!

That's the point, one needs to control which replacements take part first, right where you type isi_for_array,

and which ones occur later, upon nested execution in the remote node.

Highly recommend to watch The Matrix or Inception for more fanciful illustrations of "nested worlds"...

-- Peter