cloud-init team mailing list archive

[Scott Moser <smoser@xxxxxxxxxx>]

On Fri, May 18, 2018 at 8:01 AM, Konstantinos Papadopoulos <
kostis.g.papadopoulos@xxxxxxxxx> wrote:

> Hello,
> it also worked in my case. It was the cfg extension. Now two general
> questions
> - Is all this information described somewhere because I could not find all
> these answers in http://cloudinit.readthedocs.io
>

Welll there and in docs/ is all we have.  cloud-config is the
"#cloud-config" yaml formatted information.  Anything described in docs can
go in user-data or in a /etc/cloud/cloud.cfg.d/*.cfg file.
Those files are merged with later (alpha sort) merging "over" the others.
(see the merging section).  And user-data wins over built-in config.


> - Do you recommend using the yml syntax for executing some initial actions
> during boot or writing my own bash scripts for example? I can see the
> examples section covers a lot of cases.
>

Its really up to you.  The write-files is probably relatively easy to
maintain.  You could also use the '#include' and just launch an instance
with user-data like:
  #include http://your-site/with/your/uber/code

then you can update that code and keep the user-data you provide static



> I will use the user-data option when I will instantiate the image in our
> openstack environment.
>
>
> On Thu, May 17, 2018 at 8:14 PM, Scott Moser <smoser@xxxxxxxxxx> wrote:
>
>> My previous response inadvertently dropped the mailing list.  I've added
>> back here.
>>
>>
>>
>> On Thu, May 17, 2018 at 12:23 PM, Konstantinos Papadopoulos <
>> kostis.g.papadopoulos@xxxxxxxxx> wrote:
>>
>>> Hello Scott, I will try option b when instantiating the image in our
>>> openstack platform
>>> However what I tried not successfully was to place the file
>>> my-server-config.conf under the path /etc/cloud/cloud.cfg.d/my
>>> -server-config.conf.
>>> The content of the my-server-config.conf. file was
>>>
>>> # run commands
>>> # default: none
>>> # runcmd contains a list of either lists or a string
>>> # each item will be executed in order at rc.local like level with
>>> # output to the console
>>> # - runcmd only runs during the first boot
>>> # - if the item is a list, the items will be properly executed as if
>>> #   passed to execve(3) (with the first arg as the command).
>>> # - if the item is a string, it will be simply written to the file and
>>> #   will be interpreted by 'sh'
>>> #
>>> # Note, that the list has to be proper yaml, so you have to quote
>>> # any characters yaml would eat (':' can be problematic)
>>> bootcmd:
>>>  - [ ls, -l, / ]
>>>  - [ sh, -xc, "echo $(date) ': hello world!'" ]
>>>  - [ sh, -c, echo "=========hello world'=========" ]
>>>  - ls -l /root
>>>  - [ wget, "http://slashdot.org";, -O, /tmp/index.html ]
>>>
>>> for which I was expecting to find the index.html file under /tmp folder.
>>> However this did not happen. I guess I still miss something.
>>>
>>
>> I just tested with your bootcmd in /etc/cloud/cloud.cfg.d/my-serv
>> er-config.cfg
>> (note .cfg extension, not .conf. sorry for that).
>> that works as expected.
>>
>> Also, note though that usage of /tmp is not really safe.  that is because
>> systemd or some other thing may clean /tmp during boot.
>>
>> I tried also to fill the content of my conf file with the what you
>>> attached under http://paste.ubuntu.com/p/w8QQjN4dPC/ but without
>>> success.
>>> Is the path at l.7 correct?
>>>
>>> echo "$(date -R): Ran per-boot at ${up}s" | tee -a /run/my-per-boot.log
>>>
>>> Should it be
>>>
>>> echo "$(date -R): Ran per-boot at ${up}s" | tee -a /root/my-per-boot.log
>>>
>>> If this is the case should I expect to find the my-per-boot.log under /root?
>>>
>>>
>> In the example there, I chose /run as /run (on most linux) is a tmpfs so
>> it is guaranteed to be cleaned every boot.  I used /root on the per-once
>> messages so that you'd see that reboot did not cause that to get re-written
>> or appended to.
>>
>> As a demonstration of how to test this and to show how really nice lxd is
>> for testing cloud-init:
>>
>> $ lxc init ubuntu-daily:xenial mytest1
>> # my.cfg has content from http://paste.ubuntu.com/p/w8QQjN4dPC/
>> $ lxc file push my.cfg mytest1/etc/cloud/cloud.cfg.d/my.cfg
>> $ lxc start mytest1
>> $ sleep 5
>> $ lxc exec mytest1 cat /run/my-per-boot.log
>> Thu, 17 May 2018 17:10:53 +0000: Ran per-boot at 8.00s
>> $ lxc exec mytest1 cat /root/my-per-once.log
>> Thu, 17 May 2018 17:10:53 +0000: Ran per-once up 8.00s
>>
>> $ lxc restart mytest1
>> $ sleep 5
>> $ lxc exec mytest1 cat /run/my-per-boot.log
>> Thu, 17 May 2018 17:12:19 +0000: Ran per-boot at 4.00s
>> $ lxc exec mytest1 cat /root/my-per-once.log
>> Thu, 17 May 2018 17:10:53 +0000: Ran per-once up 8.00s
>>
>>
>> Thanks in advance
>>>
>>> Br
>>>
>>> Konstantinos
>>>
>>>
>>>
>>>
>>> On Tue, May 15, 2018 at 5:08 PM, Scott Moser <smoser@xxxxxxxxxx> wrote:
>>>
>>>>
>>>> On Tue, May 15, 2018 at 9:53 AM, Konstantinos Papadopoulos <
>>>> kostis.g.papadopoulos@xxxxxxxxx> wrote:
>>>>
>>>>> Hello Scott and thank you for the reply,
>>>>> the second option  "put scripts into /var/lib/cloud/scripts/per-boot/"
>>>>> worked as expected. So I put a script under
>>>>> /var/lib/cloud/scripts/per-boot/ and it worked.
>>>>> My question now is where am I going to store under /var/lib/cloud the
>>>>> "my-write-files" you attached which is in yml form so that I have these two
>>>>> log files written in the directories specified within the my-write-files.
>>>>> Does the file need to have a  my-write-files need to have a suffix
>>>>> .yml?
>>>>> Thanks in advance
>>>>>
>>>>
>>>> You have 2 options:
>>>> a.) a file in the system in /etc/cloud/cloud.cfg.d/your-stuff.conf
>>>> b.) provide it as user-data when you launch an instance
>>>>
>>>
>> I was wrong in 'a' above.  your-stuff.cfg (.cfg, not .conf).
>>
>>
>>>
>>>> 'b' is infinitely more flexible.
>>>>
>>>>
>
>
> --
>
> Konstantinos G. Papadopoulos, Dr-Eng.
> Software Development Engineer
> Intracom Telecom S.A., IXG
> Marinou Antipa 41, Pilaia,
> Thessaloniki, Greece, GR 57001
> tel   : +30-2310-497459 (int.: 3959)
> e-mail: konstantinos.papadopoulos@xxxxxxxxxxxx
>       : konstantinos.papadopoulos@xxxxxxxxxxx
>       : konpap@xxxxxxxxxxxxxxxxxxxx
> url   : www.intracom-telecom.com
>
> <kostis.g.papadopoulos@xxxxxxxxx>
>