[one-users] ONE context package

[ML mail]

Hi Javier,

You are right I had to define the HOSTNAME variable in the template context and not as a tag in the already running VM. This means that I can't share templates among VMs, which is a bit stupid of course. With this solution you need one template per VM. 

I see the issue with the HOSTNAME environment variable which is actually set at bootup of Linux so no problem with me for using a name such as SET_HOSTNAME like you suggest.

What do you think about having that same script also defining the hostname dynamically (if none was defined with the SET_HOSTNAME context variable) based on a DNS reverse lookup if the IP address of the VM has a PTR record?

Regards,
ML





On Thursday, February 27, 2014 12:27 PM, Javier Fontan <jfontan at opennebula.org> wrote:
 
Hi,

ML, I think you should add it in the template context section, custom variables.

I am adding scripts to configure the hostname in the context phase.
These are simple scripts (one for rpm and other for deb based distros)
that do just what you've commented, call hostname and modify the conf
file. [1]

I've just found a problem with it and it is calling the configuration
variable "HOSTNAME". The shell automatically sets HOSTNAME and even if
we don't specify it so it's a bit tricky to check wether the user
intents to configure the hostname or leave it as it is.

I am proposing to use the custom variable "SET_HOSTNAME" to configure
the host name. What do you think?

Concerning the addition of scripts in the context package, there is a
guide in both the documentation [2] and the source code [3] on how to
create custom packages. Having the required dependencies it's fairly
easy to add or modify the configuration script you may need.

Cheers

[1] http://dev.opennebula.org/issues/2453
[2] http://docs.opennebula.org/stable/user/virtual_machine_setup/cong.html#generating-custom-contextualization-packages
[3] https://github.com/OpenNebula/one/tree/master/share/scripts/context-packages

On Thu, Feb 27, 2014 at 8:02 AM, ML mail <mlnospam at yahoo.com> wrote:
> Regarding the hostname script that's exactly what I did, I also tried to
> redeploy this persistent image. Where exactly did you set the HOSTNAME
> variable? I have setted it in the tags of that specific VM (where I would
> also add the SSH_PUBLIC_KEY variable). But that might be wrong?
>
> Regards,
> ML
>
>
> On Thursday, February 27, 2014 2:47 AM, "Campbell, Bill"
> <bcampbell at axcess-financial.com> wrote:
> For item 1, no that should do it, just make sure it's executable and it
> should run. (the vmcontext init.d script will run all scripts in the
> /etc/one-context.d directory in order).  I set this up for Ubuntu, but I'm
> pretty sure Debian is the same when it comes to setting the hostname.  You
> mention you reboot the VM, you may have to redeploy (as the context script
> is already generated from your previous deployment package).
>
> For item 2, you could include it in your base image, or in the example
> provided, add it to the files repository along with that init.sh script, and
> then assign both files to the template.  This way the files will be included
> with the context information, will copy the ##-script over to the instance,
> and restart the vmcontext service.
>
> ________________________________
> From: "ML mail" <mlnospam at yahoo.com>
> To: "users" <users at lists.opennebula.org>
> Sent: Wednesday, February 26, 2014 11:12:08 AM
> Subject: Re: [one-users] ONE context package
>
> Hi Bill,
>
> Thanks for your answer and example scripts. I have a few more questions or
> issues regarding your examples:
>
> - I tried out your small hostname script which I have copied on my Debian 7
> VM under /etc/one-context.d/98-hostname. I have then set in my VM a tag
> called HOSTNAME with a value and rebooted the VM. Unfortunately the hostname
> did not get changed. Did I miss something here?
>
> - I suppose I would have to re-create the one-context package manually if I
> would like to include the aforementioned 98-hostname script in the official
> one-context package, correct? or I could manually copy it into my image
> before deploying it?
>
> Regards,
> ML
>
>
>
> On Wednesday, February 26, 2014 3:08 PM, "Campbell, Bill"
> <bcampbell at axcess-financial.com> wrote:
> We don't have the automatic lookup from DNS (that would rely on the DNS
> record being created first prior to VM deployment), but we use a script that
> is placed in our base images /etc/one-context.d/ directory that does this
> (which relies on option 2 as you mention below, a HOSTNAME context
> variable):
>
> #!/bin/bash
>
> if [ -f /mnt/context.sh ]; then
> . /mnt/context.sh
> else
> exit 0
> fi
> hostname $HOSTNAME
> echo $HOSTNAME > /etc/hostname
>
> exit 0
>
> The above example is for our Ubuntu instances, so it may need to be modified
> for RHEL or SUSE based virtuals, if that's what you use.
>
> In addition, if using 4.4, use the files datastore and create an 'init.sh'
> script that can then load up additional files that you assign to the
> template (so you don't need to manually update each image).  We use an
> init.sh script like this to inject new configuration/contextualization
> options so we don't need to update our base image very often:
>
> 
> #!/bin/sh
> #
> # OpenNebula Init Script
> #
> # init.sh
> #
> # Copies additional context scripts to the appropriate directory
> #
> ## Set environment
> SOURCE=/mnt
> DEST=/etc/one-context.d
>
> if [ -f /etc/redhat-release ]; then
> OSVERSION=RHEL
> else
> OSVERSION=UBUNTU
> fi
> if [ -f /usr/bin/rsync ]; then
> echo "Applying additional contextualization scripts..."
> else
> if [ "$OSVERSION" != "UBUNTU" ]; then
> yum -y install rsync
> else
> apt-get update && apt-get -y install rsync
> fi
> fi
>
> ## Copy Files. This will IGNORE any *.sh files in the source/destination
> directories, as all context scripts
> ## should NOT have the .sh extension.
> for i in $(ls $SOURCE --ignore=*.sh)
> do
> if [ -f $DEST/$i ]; then
> echo "$i exists in context directory. Skipping..."
> else
> rsync -au $SOURCE/$i /etc/one-context.d/
> chown root.root /etc/one-context.d/*
> chmod 700 /etc/one-context.d/*
> service vmcontext restart
> fi
> done
> exit 0
>
> This will check the OS Version and install the appropriate package.  It will
> NOT copy any file that has the .sh extension, but if you follow the context
> script standard of ##-<scriptname> then you can add additional context upon
> deployment.  Rudimentary, sure, but works well enough for us.
>
>
> ________________________________
> From: "ML mail" <mlnospam at yahoo.com>
> To: users at lists.opennebula.org
> Sent: Wednesday, February 26, 2014 5:39:46 AM
> Subject: [one-users] ONE context package
>
> Hi,
>
> I am very happy with the ONE context package for automated contextualization
> on Debian and CentOS but I miss one feature: automatically and manually
> setting the hostname of the VM.
>
> Basically it would be great to have the following two options:
>
> - automatically set the hostname of the VM based doing a reverse DNS lookup
> on the IP address, for example I have as reverse DNS entry
> "one-vm-1-0-16-172.mydomain.com" then the hostname of my VM would be
> automatically set to "one-vm-1-0-16-172".
> - using a HOSTNAME tag in the VM to manually enter a hostname and overriding
> the automatic hostname attribution described above
>
> What do you think?
>
> Regards,
> ML
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>
>
> NOTICE: Protect the information in this message in accordance with the
> company's security policies. If you received this message in error,
> immediately notify the sender and destroy all copies.
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org

>
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>
>
> NOTICE: Protect the information in this message in accordance with the
> company's security policies. If you received this message in error,
> immediately notify the sender and destroy all copies.
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>
>
>
> _______________________________________________
> Users mailing list
> Users at lists.opennebula.org
> http://lists.opennebula.org/listinfo.cgi/users-opennebula.org
>



-- 
Javier Fontán Muiños
Developer
OpenNebula - The Open Source Toolkit for Data Center Virtualization
www.OpenNebula.org | @OpenNebula | github.com/jfontan
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opennebula.org/pipermail/users-opennebula.org/attachments/20140227/f4354a6a/attachment-0002.htm>