" would also find it useful to be able to define a group as an intersection
of two groups. It's something I've wanted for a while but just haven't
gotten around to submitting a feature request for."
This is not something we'd be interested in, most likely, as it's already
doable from the host spec.
As a matter of saving time with the ticket system, always a good idea to
discuss possible features on ansible-devel first to see if we have good
solutions for them, and if we agree, maybe then it becomes a ticket.
On Thu, Aug 14, 2014 at 10:05 PM, Lorin Hochstein <
lorin.hochst...@sendgrid.com> wrote:
> I would also find it useful to be able to define a group as an
> intersection of two groups. It's something I've wanted for a while but just
> haven't gotten around to submitting a feature request for.
>
> If I use the "hosts: dbservers:&production:&northeast" syntax in N
> playbooks, then I have N opportunities to make a typo that will have very
> bad consequences (leaving out the & by mistake).
>
> Also, if I was able to define a group called
> dbservers_production_northeast, and then I decided to change the definition
> of the group, I'd only have to change it in one place. If I use it in N
> places, I'd have to go and change dbservers:&production:&northeast in N
> places. Yuck.
>
> Relying on the "--limit" argument of ansible-playbook is even more
> error-prone: there's a risk of applying the playbook to the wrong hosts
> *every time* the playbook is invoked by forgetting the --limit argument.
>
> It would be useful if ansible supported pattern syntax for defining
> children groups, so users could do something like this:
>
> [dbservers_production_northeast:children]
> dbservers:&production:&northeast
>
>
>
> On Thu, Aug 14, 2014 at 6:32 PM, Michael DeHaan <mich...@ansible.com>
> wrote:
>
>> It's not an issue of declarative vs imperative here, but saying "talk to
>> these groups".
>>
>> The children are not technically unions either, they are child
>> relationships.
>>
>>
>>
>>
>> On Thu, Aug 14, 2014 at 5:54 PM, Dominic Bou-Samra <domleb...@gmail.com>
>> wrote:
>>
>>> Perhaps I am doing it wrongly (thus the idiomatic keyword), but I find
>>> that less declarative then being able to define intersections in groups.
>>>
>>>
>>> On Friday, August 15, 2014 3:25:35 AM UTC+10, Michael DeHaan wrote:
>>>
>>>> "I can create a new a group as a union of other groups (groups of
>>>> groups), but AFAIK there's no way to create a new group as the intersection
>>>> of other groups."
>>>>
>>>> Shouldn't be needed in the inventory file, as this is something you can
>>>> address using the host spec:
>>>>
>>>> - hosts: alpha:&beta
>>>>
>>>> or also
>>>>
>>>> - hosts: alpha
>>>>
>>>> with
>>>>
>>>> ansible-playbook foo.yml --limit beta
>>>>
>>>> Either of these could be used to apply tags.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On Thu, Aug 14, 2014 at 9:42 AM, Lorin Hochstein <
>>>> lorin.h...@sendgrid.com> wrote:
>>>>
>>>>>
>>>>>
>>>>> On Thu, Aug 14, 2014 at 7:42 AM, Michael DeHaan <mic...@ansible.com>
>>>>> wrote:
>>>>>
>>>>>> "You are right about the intersection of groups - it's a shame you
>>>>>> cannot declare hosts like (excuse any syntax issues - code looks funny
>>>>>> on a
>>>>>> phone):"
>>>>>>
>>>>>> Can you elaborate on what you think is missing? ":children" to
>>>>>> define child groups is how that part works, so I'm missing the
>>>>>> understanding of what part you find lacking there.
>>>>>>
>>>>>>
>>>>> I can create a new a group as a union of other groups (groups of
>>>>> groups), but AFAIK there's no way to create a new group as the
>>>>> intersection
>>>>> of other groups.
>>>>>
>>>>> For instance, if I have a group named "atlanta" and a group named
>>>>> "webservers", there's no way to define a group called "atlanta_webservers"
>>>>> that refers to the intersection of those two groups. You have to do
>>>>> "hosts:
>>>>> atlanta:&webservers" in plays.
>>>>>
>>>>> Intersections would be really useful because I want to tag my EC2
>>>>> instances like:
>>>>>
>>>>> type=webserver
>>>>> env=production
>>>>>
>>>>> And then define a "production_webservers" group as the intersection of
>>>>> these.
>>>>>
>>>>> Lorin
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>
>>>>>> On Wed, Aug 13, 2014 at 3:12 AM, Dominic Bou-Samra <doml...@gmail.com
>>>>>> > wrote:
>>>>>>
>>>>>>> Hi Lorin,
>>>>>>>
>>>>>>> Thanks for replying.
>>>>>>>
>>>>>>> So the above presentation is exactly the solution we had arrived at
>>>>>>> in our Ansible spikes. I wish I had seen that 1 week ago :P.
>>>>>>>
>>>>>>> You are right about the intersection of groups - it's a shame you
>>>>>>> cannot declare hosts like (excuse any syntax issues - code looks funny
>>>>>>> on a
>>>>>>> phone):
>>>>>>>
>>>>>>> [staging]
>>>>>>> [staging:children]
>>>>>>> tag_env_staging
>>>>>>>
>>>>>>> [transporters]
>>>>>>> [transporters:children]
>>>>>>> tag_type_transporter
>>>>>>>
>>>>>>> [staging_transporters]
>>>>>>> [staging_transporters:children]
>>>>>>> staging
>>>>>>> transporters
>>>>>>>
>>>>>>> And then in your playbook, declare:
>>>>>>>
>>>>>>> hosts: staging_transporters
>>>>>>>
>>>>>>> But perhaps it's better to pass in variables like:
>>>>>>>
>>>>>>> // configure all staging transporters in us-east-1. Staging
>>>>>>> inventory declares group_var with staging param
>>>>>>> ansible-playbook -i staging -e zone=us-east-1 transporter.yml
>>>>>>>
>>>>>>> With transporter.yml looking like:
>>>>>>>
>>>>>>> - name: Config transporters
>>>>>>> hosts: {{environment}}:&{{zone}}:&transporters
>>>>>>>
>>>>>>> What do you think of that?
>>>>>>>
>>>>>>> On Tuesday, August 12, 2014 12:39:26 PM UTC+10, Lorin Hochstein
>>>>>>> wrote:
>>>>>>>>
>>>>>>>> Hi Dominic:
>>>>>>>>
>>>>>>>> To support mixing static with dynamic inventory, have the
>>>>>>>> "hostfile" entry in your ansible.cfg point to a directory instead of a
>>>>>>>> file. For example, my ansible.cfg contains:
>>>>>>>>
>>>>>>>> [defaults]
>>>>>>>> hostfile = inventory
>>>>>>>>
>>>>>>>> And my inventory directory looks like this:
>>>>>>>>
>>>>>>>> inventory/hosts
>>>>>>>> inventory/ec2.py
>>>>>>>> inventory/ec2.ini
>>>>>>>>
>>>>>>>> The inventory/hosts file is a static Ansible inventory file. The
>>>>>>>> inventory/ec2.py and inventory/ec2.ini are the dynamic inventory
>>>>>>>> parts. You
>>>>>>>> can edit ec2.ini to specify which regions you want, the example ec2.ini
>>>>>>>> file that ships with ansible is pretty clear on how to do this.
>>>>>>>>
>>>>>>>> I gave a talk on this topic a few months back, the slides may not
>>>>>>>> mean too much without me talking (they're pretty sparse) but here they
>>>>>>>> are:
>>>>>>>> http://go-talks.appspot.com/github.com/lorin/camp-devops-tal
>>>>>>>> k/talk.slide
>>>>>>>>
>>>>>>>> You can provision instances using the ec2 module. I recommend that
>>>>>>>> you use tags when you do provisioning because ec2.py will automatically
>>>>>>>> create groups based on tags. One gotcha here is that ec2.py will cache
>>>>>>>> by
>>>>>>>> default, so if you want to launch an instance and then configure it
>>>>>>>> immediately after it comes up, you'll need to disable caching before in
>>>>>>>> ec2.ini (set cache_max_age=0).
>>>>>>>>
>>>>>>>> If you want to do "Australian transporters in production", I don't
>>>>>>>> think you can actually define a new group as an intersection of
>>>>>>>> groups, so
>>>>>>>> you'd have to specify the hosts by explicitly doing the intersection of
>>>>>>>> groups:
>>>>>>>>
>>>>>>>> hosts: australia:&transports:&production
>>>>>>>>
>>>>>>>> (where "australia", "transports" and "production" are all groups
>>>>>>>> that I have assumed you have created via tags).
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> On Monday, August 11, 2014 3:21:47 AM UTC-4, Dominic Bou-Samra
>>>>>>>> wrote:
>>>>>>>>>
>>>>>>>>> Hi all,
>>>>>>>>>
>>>>>>>>> I've been playing with Ansible as a solution to our deployment
>>>>>>>>> infrastructure. Our stack is:
>>>>>>>>>
>>>>>>>>> - Dozens of "transporters" running on EC2.
>>>>>>>>> - Dozens of "detectors" running on EC2
>>>>>>>>> - Production and staging environments
>>>>>>>>> - Multiple regions (atm US East and Sydney)
>>>>>>>>>
>>>>>>>>> What I require from Ansible is:
>>>>>>>>>
>>>>>>>>> - A dynamic inventory, MIXED IN with a static group
>>>>>>>>> declaration. I would like to be able to refer to my "Australian
>>>>>>>>> transporters in production", as easily as possible. I would like no
>>>>>>>>> IP's/hostnames stored locally (i.e, use EC2.py as a dynamic
>>>>>>>>> inventory).
>>>>>>>>> - Ability to provision new EC2 instances in any region, in any
>>>>>>>>> environment.
>>>>>>>>> - As little duplication as possible.
>>>>>>>>>
>>>>>>>>> I am struggling with trying to lay my project out so that I can
>>>>>>>>> achieve these goals.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Could anyone provide me with some suggestions or example layouts,
>>>>>>>>> ideally with sample command? Let me know if you need more information
>>>>>>>>> and
>>>>>>>>> what I have so far
>>>>>>>>>
>>>>>>>> --
>>>>>>> You received this message because you are subscribed to the Google
>>>>>>> Groups "Ansible Project" group.
>>>>>>> To unsubscribe from this group and stop receiving emails from it,
>>>>>>> send an email to ansible-proje...@googlegroups.com.
>>>>>>>
>>>>>>> To post to this group, send email to ansible...@googlegroups.com.
>>>>>>> To view this discussion on the web visit
>>>>>>> https://groups.google.com/d/msgid/ansible-project/
>>>>>>> fb2e7d05-0664-445a-81a9-64c6b2a8ab0e%40googlegroups.com
>>>>>>> <https://groups.google.com/d/msgid/ansible-project/fb2e7d05-0664-445a-81a9-64c6b2a8ab0e%40googlegroups.com?utm_medium=email&utm_source=footer>
>>>>>>> .
>>>>>>>
>>>>>>> For more options, visit https://groups.google.com/d/optout.
>>>>>>>
>>>>>>
>>>>>> --
>>>>>> You received this message because you are subscribed to a topic in
>>>>>> the Google Groups "Ansible Project" group.
>>>>>> To unsubscribe from this topic, visit https://groups.google.com/d/
>>>>>> topic/ansible-project/Ohx3KEYwZdw/unsubscribe.
>>>>>> To unsubscribe from this group and all its topics, send an email to
>>>>>> ansible-proje...@googlegroups.com.
>>>>>>
>>>>>> To post to this group, send email to ansible...@googlegroups.com.
>>>>>> To view this discussion on the web visit https://groups.google.com/d/
>>>>>> msgid/ansible-project/CA%2BnsWgym88h0GsehetMbygfPGwzvKJ
>>>>>> TkgmNs0fabhmCdgN%2BD8w%40mail.gmail.com
>>>>>> <https://groups.google.com/d/msgid/ansible-project/CA%2BnsWgym88h0GsehetMbygfPGwzvKJTkgmNs0fabhmCdgN%2BD8w%40mail.gmail.com?utm_medium=email&utm_source=footer>
>>>>>> .
>>>>>>
>>>>>> For more options, visit https://groups.google.com/d/optout.
>>>>>>
>>>>>
>>>>> --
>>>>> You received this message because you are subscribed to the Google
>>>>> Groups "Ansible Project" group.
>>>>> To unsubscribe from this group and stop receiving emails from it, send
>>>>> an email to ansible-proje...@googlegroups.com.
>>>>> To post to this group, send email to ansible...@googlegroups.com.
>>>>> To view this discussion on the web visit https://groups.google.com/d/
>>>>> msgid/ansible-project/CACkJihNU1xdY75QXkub2yVBR19XsW
>>>>> y7zXJBsbzhu4uWu1GMH4A%40mail.gmail.com
>>>>> <https://groups.google.com/d/msgid/ansible-project/CACkJihNU1xdY75QXkub2yVBR19XsWy7zXJBsbzhu4uWu1GMH4A%40mail.gmail.com?utm_medium=email&utm_source=footer>
>>>>> .
>>>>>
>>>>> For more options, visit https://groups.google.com/d/optout.
>>>>>
>>>>
>>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Ansible Project" group.
>>> To unsubscribe from this group and stop receiving emails from it, send
>>> an email to ansible-project+unsubscr...@googlegroups.com.
>>>
>>> To post to this group, send email to ansible-project@googlegroups.com.
>>> To view this discussion on the web visit
>>> https://groups.google.com/d/msgid/ansible-project/37de6fe4-748e-444e-be96-1508ded8675c%40googlegroups.com
>>> <https://groups.google.com/d/msgid/ansible-project/37de6fe4-748e-444e-be96-1508ded8675c%40googlegroups.com?utm_medium=email&utm_source=footer>
>>> .
>>>
>>> For more options, visit https://groups.google.com/d/optout.
>>>
>>
>> --
>> You received this message because you are subscribed to a topic in the
>> Google Groups "Ansible Project" group.
>> To unsubscribe from this topic, visit
>> https://groups.google.com/d/topic/ansible-project/Ohx3KEYwZdw/unsubscribe
>> .
>> To unsubscribe from this group and all its topics, send an email to
>> ansible-project+unsubscr...@googlegroups.com.
>>
>> To post to this group, send email to ansible-project@googlegroups.com.
>> To view this discussion on the web visit
>> https://groups.google.com/d/msgid/ansible-project/CA%2BnsWgxy6d2Os1nX0ADQumK%2BRLcjKbqLv_qei7-eDy0%3DR0xqyQ%40mail.gmail.com
>> <https://groups.google.com/d/msgid/ansible-project/CA%2BnsWgxy6d2Os1nX0ADQumK%2BRLcjKbqLv_qei7-eDy0%3DR0xqyQ%40mail.gmail.com?utm_medium=email&utm_source=footer>
>> .
>>
>> For more options, visit https://groups.google.com/d/optout.
>>
>
> --
> You received this message because you are subscribed to the Google Groups
> "Ansible Project" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to ansible-project+unsubscr...@googlegroups.com.
> To post to this group, send email to ansible-project@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ansible-project/CACkJihMfwk%3D9jBENe5WsZsnjNBprGkv82kOQ3g%2BUx660CcSMZg%40mail.gmail.com
> <https://groups.google.com/d/msgid/ansible-project/CACkJihMfwk%3D9jBENe5WsZsnjNBprGkv82kOQ3g%2BUx660CcSMZg%40mail.gmail.com?utm_medium=email&utm_source=footer>
> .
>
> For more options, visit https://groups.google.com/d/optout.
>
--
You received this message because you are subscribed to the Google Groups
"Ansible Project" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to ansible-project+unsubscr...@googlegroups.com.
To post to this group, send email to ansible-project@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/ansible-project/CA%2BnsWgwLnKvTVFOJMza2hcJynNDH8%2BMOksd_tz5-Yr6rkp%2B1sA%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.
