Where's the docs?

Michal Suchánek msuchanek at suse.de
Tue Dec 20 00:26:53 AEDT 2016


On Mon, 19 Dec 2016 11:13:51 +1100
Samuel Mendoza-Jonas <sam at mendozajonas.com> wrote:

> On Fri, 2016-12-16 at 19:17 +0100, Michal Suchánek wrote:
> > Hello,
> > 
> > it seems IBM has adopted Petitboot as part of their server firmware.
> > 
> > I totally hate it. There is no documentation whatsoever.
> > 
> > I found this page
> > 
> > https://www.kernel.org/pub/linux/kernel/people/geoff/petitboot/petitboot.html
> > 
> > which has a few "man pages" with no information whatsoever how to
> > use the software and a few presentations scattered over the net
> > boasting how awesome this thing is.  
> 
> Hi Michal,
> 
> I agree that the Petitboot documentation could do with some work,
> however there are a few resources available. In particular the IBM
> Knowledge Center has several sections on Petitboot, such as
> http://www.ibm.com/support/knowledgecenter/linuxonibm/liabp/liabppetitboot.htm

I have seen this page.

I basically summarizes the options obviously available in the CUI.

Setting these options does not persist across reboot.

> 
> Jeremy Kerr also has some detailed information on his blog,
> especially this article on netboot:
> http://jk.ozlabs.org/blog/post/158/netbooting-petitboot/

This blog has these petitboot articles

- posts
 - OpenPOWER console implementations - cool diagrams of BMC console
   routing - basically inferred after reading random web pages on the
   topic
 - Toolchains for OpenPower petitboot environments - building the thing
 - Customising OpenPower firmware - building the thing
 - Netbooting with petitboot - this is useless because I do not have
   easy access to configuring a boot server. I suppose I could request
   putting a PC next to the Power system for boot configuration if
   customizing it otherwise proves futile :>

- code

  - petitboot - using petitboot on a PS3

> 
> And there are also some blog posts on the STHBRX blog, although these
> are more general-interest rather than documentation:
> https://sthbrx.github.io/

This blog has these posts

Category: Petitboot
 - Getting In Sync - modifying disk content - this is possibly one post
   that could be of some use
 - Optical Action at a Distance - using an ISO remotely - I do not need
   this because I have expanded ISOs on a boot server
 - Tell Me About Petitboot - very general post explaining why petitboot
   was made in place of one of the dozens of other possible solutions
 - No Network For You - some IPMI configuration detail, probably not
   even petitboot related
 - What the HILE is this? - technical details of endian switching
 - Petitboot Autoboot Changes - this has some CUI screenshots of stuff
   I have already seen. The only information of some use is using IPMI
   to override the boot options which should give you cooler way to
   avoid the short timeout than putting a mug on your keyboard

> 
> Additionally most screens in the Petitboot interface have an
> associated help screen that you can access with the 'h' key or the
> 'Help' button. Did you find these helpful?

Not at all. It's the typical help for the sake of having help. 

The menu is this (Excluding the device-specific options)

 *System information                                         
  System configuration
  Language
  Rescan devices
  Retrieve config from URL
  Exit to shell
 ──────────────────────────────────────────────────────────────────────────────
 Enter=accept, e=edit, n=new, x=exit, l=language, h=help

And the help for it is this:

 Petitboot help: main menu
 ──────────────────────────────────────────────────────────────────────────────
 From the main menu screen, select a boot option. The options displayed
 are available on the system and the network.

 To select a boot option, press Enter.

 To make changes to an existing option, type E (edit).

 To add a new boot option, type N (new).

 To display information about the system, including the MAC addresses
 of each network interface, type I (information).

 To make changes to the system configuration, type C (configure).

 To set the language for the petitboot interface, type L (language).

 To find new or updated boot options on the system, select the 'Rescan
 devices' option.

As is the case with such BIOS help screens they are 95% redundant to the
information already presented on the screen for which they give help.

> 
> > 
> > So what it actually does it that it scans any devices it finds for
> > any bootloader configuration it understands. Then it picks by some
> > undefined algorithm a default system to boot and timeout.  
> 
> Petitboot picks what to boot based on a) the device priority you have
> selected and b) the default option specified by the bootloader
> configuration. Do you know which version of Petitboot (or the IBM
> firmware) you are running? You should see that the device boot order
> is configurable in the "System Configuration" screen.

Options set on the CUI screens don't persist across reboots so the
order is effectively whatever petitboot picks by default. Since the
default order is not documented it's effectively random from user's
point of view.

Petitboot (dev.20150921)

> 
> > 
> > So to boot the system *you* want to boot you connect to the virtual
> > console, put a mug on your keyboard in case the timeout picked is
> > very short, select the system in the menu, etc.  
> 
> I'm very familar with the timeout problem, but you can also adjust
> the timeout value in the Configuration screen :)

Which has no effect. It seems adjusting some options on the ASMI in
power control section can affect the timeout, though. 
However, the option just magically changed from 0 or 1 to 10 again
without touching ASMI.

> 
> > 
> > There is an option to add and remove boot menu entries in the cui.
> > Sadly, I found no way to just pick the default. Also any changes are
> > lost on reboot, anyway.  
> 
> What do you mean by changes are lost on reboot? Sounds like your
> machine may have an issue there, could you provide some more detail
> on what you are seeing?

Just the same menu every time. Any deleted options are back, any added
options are lost. Any system configuration options are reset to default.

Thanks

Michal


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