Multiple clusters and attributes

Chef Infra (archive)
1

How are you guys handling attributes for multiple systems (like
clusters)??

For example, in cluster, I need to be able to add all nodes in the
cluster to the /etc/hosts file on each cluster node. I am not sure of
the best method for setting / adding attributes for these entries
without creating something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the
attribute has data. I just do not know how to populate that array
differently for different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy

2

We've got a recipe to do this... you create a role, and then an
attribute that just lists all the hostnames. The recipe then looks up
their ip addresses and writes the /etc/hosts file.

There's probably a better way to do this, but this works for us.

You can see our recipe, here:

On Fri, Apr 6, 2012 at 9:05 AM, Van Fossan,Randy vanfossr@oclc.org wrote:

How are you guys handling attributes for multiple systems (like clusters)??

For example, in cluster, I need to be able to add all nodes in the cluster
to the /etc/hosts file on each cluster node. I am not sure of the best
method for setting / adding attributes for these entries without creating
something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the attribute
has data. I just do not know how to populate that array differently for
different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy

3

Thanks Brad,

There are some nice things in that cookbook that I may rethink in my hosts cookbook.

However, the issue for specifying all the nodes in a cluster when running the bootstrap on a particular node remains.

The only solution I have come up with is to use a databag that describes each cluster and it's nodes or to create a custom role for each cluster..

Randy

-----Original Message-----
From: bkmontgomery@gmail.com [mailto:bkmontgomery@gmail.com] On Behalf Of Brad Montgomery
Sent: Friday, April 06, 2012 11:09 AM
To: chef@lists.opscode.com
Subject: [chef] Re: multiple clusters and attributes

We've got a recipe to do this... you create a role, and then an attribute that just lists all the hostnames. The recipe then looks up their ip addresses and writes the /etc/hosts file.

There's probably a better way to do this, but this works for us.

You can see our recipe, here:

On Fri, Apr 6, 2012 at 9:05 AM, Van Fossan,Randy vanfossr@oclc.org wrote:

How are you guys handling attributes for multiple systems (like clusters)??

For example, in cluster, I need to be able to add all nodes in the
cluster to the /etc/hosts file on each cluster node. I am not sure
of the best method for setting / adding attributes for these entries
without creating something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the
attribute has data. I just do not know how to populate that array
differently for different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy

4

A cluster sounds like it could be a chef environment. could you just have a
recipe in which each node uses the search API to find all nodes in the
environment?

KC
On Apr 6, 2012 8:28 AM, "Van Fossan,Randy" vanfossr@oclc.org wrote:

Thanks Brad,

There are some nice things in that cookbook that I may rethink in my hosts
cookbook.

However, the issue for specifying all the nodes in a cluster when running
the bootstrap on a particular node remains.

The only solution I have come up with is to use a databag that describes
each cluster and it's nodes or to create a custom role for each cluster..

Randy

-----Original Message-----
From: bkmontgomery@gmail.com [mailto:bkmontgomery@gmail.com] On Behalf Of
Brad Montgomery
Sent: Friday, April 06, 2012 11:09 AM
To: chef@lists.opscode.com
Subject: [chef] Re: multiple clusters and attributes

We've got a recipe to do this... you create a role, and then an attribute
that just lists all the hostnames. The recipe then looks up their ip
addresses and writes the /etc/hosts file.

There's probably a better way to do this, but this works for us.

You can see our recipe, here:
GitHub - coroutine/chef-hosts: This cookbook creates host aliases

On Fri, Apr 6, 2012 at 9:05 AM, Van Fossan,Randy vanfossr@oclc.org
wrote:

How are you guys handling attributes for multiple systems (like
clusters)??

For example, in cluster, I need to be able to add all nodes in the
cluster to the /etc/hosts file on each cluster node. I am not sure
of the best method for setting / adding attributes for these entries
without creating something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the
attribute has data. I just do not know how to populate that array
differently for different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy

5

Just to be clear, I create a single role for the cluster, and specify
all nodes in that role. Then, apply that role to every machine. I'm
not sure I made that clear in my last email, and I'm sure there's
probably a better way to do it. I've also done similar things to what
you've described in a data bag.

Do all of your clusters also need to know about each other?

On Fri, Apr 6, 2012 at 10:27 AM, Van Fossan,Randy vanfossr@oclc.org wrote:

Thanks Brad,

There are some nice things in that cookbook that I may rethink in my hosts cookbook.

However, the issue for specifying all the nodes in a cluster when running the bootstrap on a particular node remains.

The only solution I have come up with is to use a databag that describes each cluster and it's nodes or to create a custom role for each cluster..

Randy

-----Original Message-----
From: bkmontgomery@gmail.com [mailto:bkmontgomery@gmail.com] On Behalf Of Brad Montgomery
Sent: Friday, April 06, 2012 11:09 AM
To: chef@lists.opscode.com
Subject: [chef] Re: multiple clusters and attributes

We've got a recipe to do this... you create a role, and then an attribute that just lists all the hostnames. The recipe then looks up their ip addresses and writes the /etc/hosts file.

There's probably a better way to do this, but this works for us.

You can see our recipe, here:
GitHub - coroutine/chef-hosts: This cookbook creates host aliases

On Fri, Apr 6, 2012 at 9:05 AM, Van Fossan,Randy vanfossr@oclc.org wrote:

How are you guys handling attributes for multiple systems (like clusters)??

For example, in cluster, I need to be able to add all nodes in the
cluster to the /etc/hosts file on each cluster node. I am not sure
of the best method for setting / adding attributes for these entries
without creating something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the
attribute has data. I just do not know how to populate that array
differently for different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy

6

Roles as data is OK, depending on what you need and what you're dealing
with.

Just make sure you've got a good naming scheme so that it's crystal clear
which roles are part of your infrastructure's code (and therefore are saved
as Ruby files in your Git repository) and which roles are part of your
infrastructure's data (and therefore are only known to the Chef Server and
then only as pure JSON, and never touch your disk or your Git repository or
any of the infrastructure's Ruby code).

For example, you could name a role of the second category something like
dyna-hosts-cluster-88b639a3, where in this example the prefix dyna- for any
role in the example's infrastructure is defined to mean a role of the
second category. This is just an example, of course, so pick a naming
scheme that works for you.

Cheers,
Jay Feldblum

On Fri, Apr 6, 2012 at 1:38 PM, Brad Montgomery brad@bradmontgomery.netwrote:

Just to be clear, I create a single role for the cluster, and specify
all nodes in that role. Then, apply that role to every machine. I'm
not sure I made that clear in my last email, and I'm sure there's
probably a better way to do it. I've also done similar things to what
you've described in a data bag.

Do all of your clusters also need to know about each other?

On Fri, Apr 6, 2012 at 10:27 AM, Van Fossan,Randy vanfossr@oclc.org
wrote:

Thanks Brad,

There are some nice things in that cookbook that I may rethink in my
hosts cookbook.

However, the issue for specifying all the nodes in a cluster when
running the bootstrap on a particular node remains.

The only solution I have come up with is to use a databag that describes
each cluster and it's nodes or to create a custom role for each cluster..

Randy

-----Original Message-----
From: bkmontgomery@gmail.com [mailto:bkmontgomery@gmail.com] On Behalf
Of Brad Montgomery
Sent: Friday, April 06, 2012 11:09 AM
To: chef@lists.opscode.com
Subject: [chef] Re: multiple clusters and attributes

We've got a recipe to do this... you create a role, and then an
attribute that just lists all the hostnames. The recipe then looks up their
ip addresses and writes the /etc/hosts file.

There's probably a better way to do this, but this works for us.

You can see our recipe, here:
GitHub - coroutine/chef-hosts: This cookbook creates host aliases

On Fri, Apr 6, 2012 at 9:05 AM, Van Fossan,Randy vanfossr@oclc.org
wrote:

How are you guys handling attributes for multiple systems (like
clusters)??

For example, in cluster, I need to be able to add all nodes in the
cluster to the /etc/hosts file on each cluster node. I am not sure
of the best method for setting / adding attributes for these entries
without creating something like a separate role for each cluster.

I already have a hosts cookbook to add additional entries if the
attribute has data. I just do not know how to populate that array
differently for different clusters.

Anyone have any suggestions or ideas?

Thanks
Randy