RE: Copy to multiple destinations

[Luke Youngblood]

Good post.  I have been contemplating how to implement cfengine on some of our clustered servers as well.  Although I haven’t implemented it yet, I think this can safely be done using the FileExists class.  The logic is that if the clustered filesystem isn’t mounted, certain files won’t exist, therefore, you can skip the relevant copy section on that server.  The limitation is that you have to write every possibility into your file.  Here is a quick implementation that I wrote up in a few minutes:

 

control:

 

   actionsequence = ( copy )

 

classes:

 

   primary_node_AA = FileExists (/some/path/AA/network/admin/tnsnames.ora)

   primary_node_AB = FileExists (/some/path/AB/network/admin/tnsnames.ora) 

   primary_node_AC = FileExists (/some/path/AC/network/admin/tnsnames.ora)

   <snip>

 

copyfiles:

 

   primary_node_AA::

 

      (copy statements go here)

 

   primary_node_AB::

 

      (copy statements go here)

 

   primary_node_AC::

 

      (copy statements go here)

 

Essentially, you list each one of your clustered filesystems and set a class if the tnsnames.ora file exists on that filesystem.  If so, the copy statement gets evaluated.   If not, it gets skipped.

 

HTH,

 

Luke

 

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From: help-cfengine-bounces+lyoungblood=phonechargeinc.com@gnu.org [mailto:help-cfengine-bounces+lyoungblood=phonechargeinc.com@gnu.org] On Behalf Of Martin, Jason H
Sent: Tuesday, June 07, 2005 8:35 PM
To: help-cfengine@gnu.org
Subject: Copy to multiple destinations

 

Is there any way to have a file copied to a variable number of destinations?  I'm looking for a way to keep a set of Oracle installations in sync.  Since the boxes are clustered, there is a set of hosts which may have 0 or more oracle installations in seperate directories under /some/path.  Each directory has a file network/admin/tnsnames.ora. There is supposed to be just one master copy of tnsnames.ora, so I'd like Cfengine to copy the gold tnsnames.ora to /some/path/XX/network/admin/tnsnames.ora, where XX is a list of directories populated in a variable by a module or (preferably) a wildcard expansion that is then evaulated by a filter. However, there doesn't seem to be any way in Cfengine to express this.

Since the number of directories under /some/path is variable, it isn't feasible to write individual stanzas for each directory as a filesystem may be unmounted and moved to another host at any time.  The filesystems are SAN-based, so unlike a NFS server there is no 'central home' where it would be reasonable to hardcode each individual directory into a stanza.

As it happens, each /some/path/XX is a home directory, but they aren't all Oracle installations and so copying it to just 'homes/network/admin/tnsnames.ora' doesn't seem very elegant.

I am looking at several scenarios like this, so the solution can't be Oracle specific (as in 'use Oracle Internet Directory' or 'define TNS_ADMIN to a central directory'), however the Oracle one is the easiest to explain.

I have a feeling that the underlying problem is the same one mentioned at http://lists.gnu.org/archive/html/help-cfengine/2005-04/msg00094.html, and that CFE 3 is the only solution aside from a custom shellcommand. However, I thought I would ask anyway. Does anyone have any suggestions on how I might approach this?

Thanks,
-Jason Martin