Building on the initial post about cfengine we’re going to try out some things that may actually be useful.
My goal would be to make /etc/resolv.conf identical between all the machines.
The server setup is the lustre cluster we built in a previous post.
In this post you’ll first see two attempts at getting cfengine and then puppet to do my bidding until success was finally accomplished with salt.
Set up name resolution to be identical on all machines.
Make oss1 and client1 not get the same promises.
Perhaps some kind of rule / IF-statement in the promise?
Cfengine feels archaic. Think editing named/bind configs are complicated? They are not even close to setting up basic promises in cfengine.
vi /etc/yum.repos.d/puppet.repo pdcp -w oss1,client1 /etc/yum.repos.d/puppet.repo /etc/yum.repos.d/puppet.repo
puppet cert list puppet cert sign sudo puppet cert sign --all
For puppet there’s a dashboard. This sounds interesting. Perhaps I won’t have to write these .pp files which at a glancelooks scarily similar to the cfengine promises.
yum install puppet-dashboard mysqld
service start mysqld
set mysqld password
create databases (as in the database.yml file)
after this I didn’t get much further… But I did get the web-server up. Although it was quite empty…
Easy startup instructions here for getting a parallel shell going:
After it’s set up you can run a bunch of built-in special commands, see the help section about modules.
salt ‘*’ sys.doc|less
will give you all the available modules you use :)
Want to use it for configuration management too? Check out the ‘states‘ section.
What looks bad with salt is that it’s a quite new (first release in 2011)
Salt is a very common word so it makes googling hard. Most hits tend to be about cryptography or cooking.
To distribute (once) the resolv.conf do you run this on the admin-server: salt-cp ‘*’ /etc/resolv.conf /etc/resolv.conf
On to states to make sure that the resolv.conf stays the same:
- uncomment the defaults in the master-file about file_roots and restart the salt-master service
- create /srv/salt and ln -s /etc/resolv.conf /srv/salt/resolv.conf
- create a /srv/salt/top.sls and a /srv/salt/resolver.sls
In top.sls put:
base: '*': - resolver
In resolver.sls put:
/etc/resolv.conf: file: - managed - source: salt://resolv.conf
Then run: salt ‘*’ salt.highstate
How to get this to run every now and then? Setting up a cronjob works.
Haven’t been able to find a built-in function to accomplish this but then again, all I’m doing here is scratching at the surface so it’s working and I’m happy :)