[Users] More on making an OpenVZ template

[Benjamin Henrion]

On Sun, Aug 21, 2011 at 4:10 PM, Kir Kolyshkin <kir at openvz.org> wrote:
> On 08/20/2011 12:18 AM, Sam Trenholme wrote:
>>
>> I am continuing the work of making a tiny OpenVZ template.  One
>> discovery I have is that, for the OpenVZ tools to work, not only is it
>> mandatory for the system to have the Bash shell, but also that /bin/sh
>> has to be a symlink to Bash.  This is because the "vzctl" program
>> prepends the contents of the Bash-only
>> "/etc/vz/dists/scripts/functions" script to any script used by the
>> container to configure the system, and there does not appear to be any
>> way to configure a container to not use this Bash-only script.
>>
>> In other words, any OpenVZ template without /bin/sh being an alias for
>> Bash can not be configured via the "vzctl" tools (nor the
>> corresponding Proxmox/SolusVM/whataever tools that call "vzctl").
>>
>> This in mind, the next release of TinyVZ will include the Bash shell.
>> I actually prefer Bash over Busybox's "ash" shell; I *really* miss the
>> "!$" and "!*" shortcuts, as well as the "history" command, when using
>> this minimal shell.
>
> This is one way of doing things. The other way would be to rectify the
> '/etc/dists/scripts/functions' to not be dependent on bash.
>
> I am currently looking at it, so far I only found that it uses the
> 'function' keyword
> which is bashism. With that removed, it looks like it is working fine in
> either dash
> or busybox sh.
>
> I have committed the patch:
> http://git.openvz.org/?p=vzctl;a=commit;h=f83b28435f582f2f74fb3267b89b061a551b32e2
>
> And then a few more (to check it works in Debian without /bin/bash):
> http://git.openvz.org/?p=vzctl;a=commit;h=a86beacde8c1fba4002eaf5bf48a535e7d46ffc0
> http://git.openvz.org/?p=vzctl;a=commit;h=382f306cd0865bb4bcafc4f7a4b5cfe2f809296c

I have compiled it, and I can report it works, I have remove the bash
binary I got from tinyvz, and now it enters well in openwrt rootfs (I
have tested with the original vzctl 3.0.24 where it fails to enter if
there is no /bin/bash):

==================================================
root at mybox /root/zoobab/openwrt-openvz [46]# ./vzctl --version
vzctl version 3.0.28.3-70.git.382f306
root at mybox /root/zoobab/openwrt-openvz [40]# ./vzctl enter 889
entered into CT 889


BusyBox v1.15.3 (2011-07-14 17:03:04 CEST) built-in shell (ash)
Enter 'help' for a list of built-in commands.

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          |__| W I R E L E S S   F R E E D O M
 Backfire (10.03.1-RC5, r27608) --------------------------
  * 1/3 shot Kahlua    In a shot glass, layer Kahlua
  * 1/3 shot Bailey's  on the bottom, then Bailey's,
  * 1/3 shot Vodka     then Vodka.
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root at OpenWrt:/#
==================================================

-- 
Benjamin Henrion <bhenrion at ffii.org>
FFII Brussels - +32-484-566109 - +32-2-4148403
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