I'm working on a tool which manages WordPress instances using puppet. The flow is the following: the user adds the data of the new WordPress installation in the web interface and then that web interface is supposed to send a message to the puppet master to tell it to deploy it to the selected machine.
Currently the setup is done via a manifest file which contains the declaration of all WordPress instances, and that is applied manually via puppet apply on the puppet agent. This brings me to my 2 questions:
Are manifests the correct way of doing this? If so, is it possible to apply them from the puppet master to a specific node instead of going to the agent?
Is it possible to automatically have a puppet run triggered once the list of instances is altered?
To answer your first question, yes there's absolutely a way of doing this via a puppetmaster, what you have at the moment is a masterless setup which assumes you're distributing your configuration with some kind of version control (like git) or manual process. This is a totally legitimate way of doing things if you don't want a centralized master.
If you want to use a master, you'll need to drop your manifest in the $modulepath of your master (it varies depending on your version, you can find it using puppet config print modulepath on your master) and then point the puppet agent at the master.
If you want to go down the master route, I'd suggest following the puppet documentation which will help you get started.
The second question brings me on to a philosphical argument of 'is this really want you want to do?'
Puppet traditionally (in my opinion) is a declarative config management tool that is designed to make your systems look a certain way. You write code to determine 'this is how I want it to look' and Puppet will converge to make it look that way. What you're looking to do is more of an orchestration task (ie when X do Y). There are ways of doing this with Puppet like using mcollective (to trigger a puppet run) which is managed by a webhook, but I think there are better tools for the job.
I'd suggest looking at ansible, saltstack or Chef's knife tool to do deploys like this.
Related
I'm using the ibm_installation_manager module from the puppet forge and it is a bit basic because IBM wrote Installation Manager in a time where idempotency was done much.
ref: https://forge.puppet.com/puppetlabs/ibm_installation_manager
As such it does not cater nicely for upgrades - so the module will not detect if an upgrade is needed, stop existing processes, do the upgrade and then start the processes again. It will just detect if an upgrade is needed and try to install the desired version and if that constitutes an upgrade that's great, but it will probably fail due to running instances.
So I need to implement some "stop processes" pre-upgrade functionality.
I need to mention at this point I'm new to ruby and fairly new to puppet.
The provider that the module uses (imcl.rb) has an exists method.
The ideal way for me to detect if an upgrade is going to happen (and stop the instances if it is) would be for my puppet manifest to be able to somehow call the exists method. Is this possible?
Or how would you approach this problem?
Something like imcl.exists(ibm_pkg["my_imcl_pkg_resource"])
The ideal way for me to detect if an upgrade is going to happen (and stop the instances if it is) would be for my puppet manifest to be able to somehow call the exists method. Is this possible?
No, it is not possible, at least not in any useful way. Your manifests describe how to build a catalog of resources describing the target state of the machine. In a master / agent setup, this happens on the master. The catalog is then used as input to a separate step, in which it is transferred to the target machine and applied there. It is in this second step that providers are engaged.
To the extent that you want the contents of your catalogs to be influenced by the current state of the target machine, the Puppet mechanism for that is to convey the needed state details to the catalog builder in the form of facts. It is relatively straightforward to add your own facts. Indeed, there are at least two distinct, non-exclusive mechanisms, going under the names "external facts" and "custom facts".
i have puppet master and node/agent setup configured manually. using the self signed certificates by master, all client nodes are bootstrapped and now they are under puppet master controlled. i mean registered with puppet master.
i have done this registration manually using commands like puppet cert sign and puppet agent --test and puppet cert list etc
however, my question is, what is the best automatic way to bootstrap a particular node..
1: Is it recommended that , write shell script (on UNIX) and get these commands automated ? any better way ?
2: does puppet already provides an automated configuration/resource which i can simply call in someway and get node registered ?
please suggest.
Regards,
you can get very close to your goal with external node classifiers and autosigning
i used this to fully automate the process of creating and deploying virtual machines.
There is the need that one puppet agent contacts some different puppet masters.
Reason: there are different groups that create different and independent sets of manifests.
Possible groups and their tasks
Application Vendor: configuration of application
Security: hardening
Operations: routing tables, monitoring tools
Each of these groups should run it's own puppet master - the data (manifests and appropriate data) should be strictly separated. If it is possible, one group should even not see / have access to the manifests of the others (we are using MAC on the puppet agent OSes).
Thoughts and ideas that all failed:
using (only) hira is not flexible as needed - there is the need to have different manifests.
r10k: supports more than one environment, but in each environment can only access one set of manifests.
multi but same puppet server using e.g. DNS round robin: this is the other way round. We need different puppet masters.
Some ways that might be possible but...
running multiple instances of puppet agents. That 'feels' strange. Advantage: the access rights can be limited in the way as needed (e.g. the application puppet agent can run under the application user).
patching puppet that it can handle more than one puppet master. Disadvantage: might be some work.
using other mechanisms to split responsibility. Example: use different git-repositories. Create one puppet master. The puppet master pulls all the different repositories and serves the manifests.
My questions:
Is there a straight forward way implementing this requirement with puppet?
If not, is there some best practice how to do this?
While I think what you are trying to do here is better tackled by incorporating all of your modules and data onto a single master, and that utilizing environments will be effectively the exact same situation (different masters will provide a different set of modules/data) this can be achieved by implementing a standard multi-master infrastructure (one CA master for cert signing, multiple compile masters with certs signed by the same CA master, configured to forward cert traffic elsewhere) and configure each master to have whatever you need. You then end up having to specify which master you want to check in to on each run (a cronjob or some other approach), and have the potential for one checkin to change settings set by another (kinda eliminating the hardening/security concept).
I would urge you to think deeper on how to collaborate your varied aspects (git repos for each division's hiera data and modules that have access control) so that a central master can serve your needs (and access to that master would be the only way to get data/modules from everywhere).
This type of setup will be complex to implement, but the end result will be more reliable and maintainable. Puppet inc. may even be able to do consultation to help you get it right.
There are likely other approaches too, just fyi.
I've often found it convenient to multi-home a puppet agent for development purposes, because with a local puppet server you can instantly test manifest changes - there's no requirement to commit, push and r10k deploy environment like there is if you're just using directory environments and a single (remote) puppet server.
I've found the best way to do that is to just vary the path configuration (otherwise you run into problems with e.g. the CA certs failing to verify against the other server) - a form of your "running multiple instances of puppet agents" suggestion. (I still run them all privileged, so they can all use apt package {} etc.)
For Puppet 3, I'd do this by varying the libdir with --libdir (because the ssldir was under the libdir), but now (Puppet 4+) it looks more sensible to vary the --confdir. So, for example:
$ sudo puppet agent -t # Runs against main puppet server
$ sudo puppet agent -t \
--server=puppet.dev.example.com \
--confdir=/etc/puppetlabs/puppet-dev # Runs against dev puppet server
I am trying to understand the best practice of setting up Puppet in the first place, let's say I have 1000 existing servers needs to be managed Puppet.
Do I manually install Puppet agent on each or there is a better way.
Sorry if this question is too generic just want to have some idea.
1000 servers could be a lot for a single master instance. of course it will depend on the master specs, and other factors related to the puppet runs.
There are few questions you need to answer first to determine how are you going to go about it such as
Puppet Enterprise or Open Source? What is the current configuration night mare you are trying to solve?
What is the current configuration data related to the challenge or
problem you have?
What are the current business roles (e.g. web server, load
balancer,database, ..etc) related to the problem you have? What
makes a role in terms of configurations?
I would suggest that you start first small to learn more about the puppet DSL, and its ECO system (master, agent, puppetdb, console/dashboard). I also recommend you start with the free 10 nodes puppet Enterprise as it will let you focus more on the problem at hand not how to configure the puppet masters, and agents, how to scale them, ..etc.
One more thing install puppet agent every where if you can in NOOP/disabled mode to get at least facts and run it in a masterless fashion using puppet apply when you need to. i find NOOP mode more useful as it tells you what needs to be changed, also you can enforce changes using --no-noop
hope that will get you started.
To answer your question: Yes, Puppet agent would need to be installed on every node. If you are managing 1000 nodes, I would assume you have your own OS image. In this case, its best to add it to the OS image, and use this image on 1000 nodes.
Is there a built-in way to mass deploy the Puppet agent on hundreds of nodes, in an unattended, automated way? (providing user/pass/cert.)
There is no built in way to do so. But, you can always use kickstart/pre-seed to deploy puppet agent as part of os provisioning and hand it to puppet to manage your hosts.
Or as an alternate you can write custom shell script to deploy puppet agent's on hundreds on machines, I personally use this method to manage puppet. For reference here is the script.
Also, you may be interested in project razor which automatically deploys puppet as part of bare-metal provisioning and hands it to puppet for configuration management.
Basically the only thing you need to do is to install the Puppet Agent on those machines. I assume that you don't install software packages manually for hundreds of nodes, right?
Once you installed the Agent, it will automatically find the Puppet Master (if puppet.yourdomain.com points to that host), sends certificate requests to the Master where you need to sign them. You can also use the autosign feature of Puppet.
Furthermore, Puppet Enterprise and The Foreman are bases on Puppet and they come along with additional provisioning features.
I suggest that you use the parallel SSH. There are plenty of flavours, I prefer clush, see https://github.com/cea-hpc/clustershell/wiki/clush
You need to create your /etc/clustershell/groups file with groups, e.g.:
all: node[1-2000]
Then you can install the puppet on all the nodes easily with something like this:
clush -bw #all yum -y install puppet