[vcf-midatlantic] Monitor needed for museum

Dean Notarnicola dnotarnicola at gmail.com
Sat Aug 26 14:56:46 EDT 2017


Power banks are notorious for leaking power, and ones that can be left
in-line (simultaneous charges and power) are expensive.

On Sat, Aug 26, 2017 at 2:36 PM Dave Wade via vcf-midatlantic <
vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:

> I do know that PI's are famous for corrupting the boot disk. A couple of
> work arounds, use a cheap phone booster as a UPS,
>
> http://raspi-ups.appspot.com/en/index.jsp
>
>
> or change the PI to boot from USB stick.
>
> An old article on this is here:-
>
>
> https://samhobbs.co.uk/2013/10/speed-up-your-pi-by-booting-to-a-usb-flash-dr
> ive
>
> Dave
>
>
>
> > -----Original Message-----
> > From: vcf-midatlantic [mailto:vcf-midatlantic-
> > bounces at lists.vintagecomputerfederation.org] On Behalf Of Jim Scheef via
> > vcf-midatlantic
> > Sent: 26 August 2017 14:50
> > To: William Dudley via vcf-midatlantic <vcf-
> > midatlantic at lists.vintagecomputerfederation.org>
> > Cc: Jim Scheef <js at sdf.org>
> > Subject: Re: [vcf-midatlantic] Monitor needed for museum
> >
> > Could I ask a question? How often does this happen? Ok, two questions...
> > what happens when the power goes off? (No talk about how reliable the
> > power is at IA.) Just pull the f%^&ing plug and reboot the Pi. It has a
> > journaling file system and will check the file system if needed. Why all
> the
> > fuss?
> > Occasionally it might be a good idea to make a copy of the uSD card as a
> > backup.
> > Jim
> >
> >
> > On Wed, 23 Aug 2017, William Dudley via vcf-midatlantic wrote:
> >
> > > Date: Wed, 23 Aug 2017 09:31:40 -0400
> > > From: William Dudley via vcf-midatlantic
> > >     <vcf-midatlantic at lists.vintagecomputerfederation.org>
> > > To: vcf-midatlantic
> > > <vcf-midatlantic at lists.vintagecomputerfederation.org>
> > > Cc: William Dudley <wfdudley at gmail.com>
> > > Subject: Re: [vcf-midatlantic] Monitor needed for museum
> > >
> > > We are currently trying to install the shutdown button and associated
> > > script, but couldn't install the script as we lost the ability to ssh
> > > into the pi. So we can't power it down properly, we can't edit config
> > > files, and we can't fix ssh without the monitor.
> > >
> > > Bill Dudley
> > >
> > >
> > > On Aug 23, 2017 8:30 AM, "Neil Cherry via vcf-midatlantic" <
> > > vcf-midatlantic at lists.vintagecomputerfederation.org> wrote:
> > >
> > >> On 08/22/2017 08:21 PM, David Ryskalczyk via vcf-midatlantic wrote:
> > >>
> > >>> I'll make an EE guess here: When you unplug the DC side, the Pi is
> > >>> shut off relatively quickly so there is little room for bad writes
> > >>> to corrupt the card, or for the voltage to drop low enough for the
> > >>> CPU to execute random instructions but still high enough to run at
> > >>> all. When you unplug the AC side of the power adapter, the
> > >>> capacitance in the power supply causes a much slower drop-off which
> > >>> causes the CPU to execute random instructions, likely writing to the
> > >>> card.
> > >>>
> > >>
> > >> I think the USB PS tend to be more inductive than capacitive.
> > >>
> > >> My suggestions? Make the Linux setup as read-only as possible as that
> > >> will
> > >>> minimize
> > >>> possibility of corruption, and of course, if the image contents are
> > >>> static, keep a copy of the image handy on a nearby PC. Constant
> > >>> writing will quickly kill the SD card anyway.
> > >>>
> > >>
> > >> This will help, you can setup a share using either NFS or Samba
> (CIFS).
> > >> You can then write to that.
> > >>
> > >> But there are some things that need to write to files. The OS part of
> > >> Linux generally doesn't need this but the applications (rsyslog,
> > >> email, etc) does and they also tend to try and write out logs. That's
> > >> a distribution issue.
> > >>
> > >> Pulling power from the DC end (that part that plugs into the Pi
> > >> directly) is probably not a bad idea. But not until you've run the
> shutdown
> > cmd.
> > >> So to properly shutdown the Pi, run the shutdown command or use
> > >> Dave's suggestion of the pushbutton solution. I like that one but
> > >> protect the button and don't make it a big red button that say don't
> > >> push. People will want to push it.
> > >>
> > >> I'm sure there are more than a few of us with stories of idiots
> > >> pushing the emergency power off on mainframes.
> > >>
> > >> --
> > >> Linux Home Automation         Neil Cherry       ncherry at linuxha.com
> > >> http://www.linuxha.com/                         Main site
> > >> http://linuxha.blogspot.com/                    My HA Blog
> > >> Author of:      Linux Smart Homes For Dummies
> > >>
> > >
> >
> > js at sdf.org
> > SDF Public Access UNIX System - http://sdf.lonestar.org
>
>



More information about the vcf-midatlantic mailing list