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- Monday, December 8, 2014
- ========================
-
- ssh
- ---
-
- I use SSH for damn near everything. We need SSH for damn near everything.
-
- I have this thought that SSH is quite possibly the only end-user-exposed
- implementation of acceptable crypto in wide use which actually satisfies the
- "actual human beings can use this" constraint at the same time as satisfying
- the "this makes your shit relatively secure" constraint. That's not to say
- it's easy for the average mortal to comprehend, but it beats the shit out of
- almost everything else I can think of.
-
- In "almost everything else", I include SSL/TLS/HTTPS, which sort-of works as
- far as the general user population of browsers is concerned, much of the time,
- but which is an absolute nightmare to administer and which is a fundamentally
- broken design on a political / systems-of-control / economic /
- regular-admins-get-this-right level. Arguably, the only thing that has been
- worse for the wide adoption of crypto by normal users than SSL/TLS is PGP.
-
- DISCLAIMER: I DON'T KNOW SHIT ABOUT CRYPTO. Tell me how I'm wrong.
-
- -> ✴ <-
-
- * "[Sorry Theo, but SSH Sucks](http://harmful.cat-v.org/software/ssh)"
-
- mosh
- ----
-
- I'm not exactly sure when mosh started to catch on with people I know, but I'd
- say it's on the order of a year or two that I've been aware of it. The basic
- thing here is that it's essentially OpenSSH with better characteristics for a
- specific cluster of use cases:
-
- - laggy, high-latency, intermittently-broken network connections
- - client machines that frequently hop networks and/or suspend operations
- - unreliable VPNs (which is to say very nearly all VPNS in actual use)
-
- time tracking
- -------------
-
- I'm about to start in on some remote contracting stuff, so I go looking for a
- time tracking tool. For the moment I settle on this little tray widget called
- [hamster](http://projecthamster.wordpress.com/), which looks functional if not
- precisely inspiring.
-
- noobs / raspbian
- ----------------
-
- Last year I did a bunch of work on a Raspberry Pi, but it's been a few months
- since I booted one up. I got a model B+ (more USB ports, various hardware
- tweaks, takes a microSD card instead of the full-size one) in my last employee
- order at SparkFun, and I'm stepping through what seems to be the stock
- recommended installation process.
-
- - http://www.raspberrypi.org/new-raspbian-and-noobs-releases/
- - http://www.raspberrypi.org/downloads/
- - http://downloads.raspberrypi.org/NOOBS_latest.torrent
-
- I torrented `NOOBS_v1_3_10.zip`. Be careful unzipping this one - everything is at
- the top level of the archive (advice to distributors of basically anything: don't
- do that).
-
- If I'd been smart I probably would have done:
-
- $ mkdir noobs && unzip NOOBS_v1_3_10.zip -d noobs/
-
- The basic system here is "get an SD card, put the stuff in this zip file on the
- SD card, put it in the Pi". Everything about this has always felt kind of
- weird (if not actively broken) to me, but it's probably important to remember
- that for most users "put some files on this media" is a lot easier than "image
- this media with the filesystem contained in this file".
-
- -> ✩ <-
-
- So I plug in all the stuff: microSD card, keyboard, HDMI cable to random spare
- monitor, power.
-
- Nothing. Well, almost nothing. Blinkenlights, no video output. Red light is
- steady, green light blinks a couple of times periodically.
-
- I am reminded that this is, fundamentally, a terrible piece of hardware.
-
- Power down, remove SD card, mount SD card on Linux machine, google variously,
- delete and recreate FAT32 partition using gparted, re-copy NOOBS files, unmount
- SD card, replace card in Pi, re-apply power.
-
- Green LED flashes spasmodically for a bit then seems mostly off, but is actually
- flickering faintly on closer examination. Red light is solid.
-
- [This wiki page](http://elinux.org/R-Pi_Troubleshooting#Red_power_LED_is_on.2C_green_LED_does_not_flash.2C_nothing_on_display)
- suggests this means that no boot code has been executed at all. It's failing to
- read the card, or it's missing some file, or something is corrupt.
-
- Ok, so, mount SD card on Linux machine again; immediately discover that the
- card is now a volume called "SETTINGS", or seems to be.
-
- $ ls /media/brennen/SETTINGS
- lost+found
- noobs.conf
-
- $ cat /media/brennen/SETTINGS/noobs.conf
- [General]
- display_mode=0
- keyboard_layout=gb
- language=en
-
- brennen@desiderata 15:52:24 /home/brennen ★ sudo parted /dev/mmcblk0
- GNU Parted 2.3
- Using /dev/mmcblk0
- Welcome to GNU Parted! Type 'help' to view a list of commands.
- (parted) print
- Model: SD SL16G (sd/mmc)
- Disk /dev/mmcblk0: 15.9GB
- Sector size (logical/physical): 512B/512B
- Partition Table: msdos
-
- Number Start End Size Type File system Flags
- 1 1049kB 823MB 822MB primary fat32 lba
- 2 826MB 15.9GB 15.1GB extended
- 3 15.9GB 15.9GB 33.6MB primary ext4
-
- (parted)
-
- Well, obviously something ran, because I definitely didn't arrange anything
- that way. And this seems a little telling:
-
- brennen@desiderata 15:55:36 /home/brennen ★ dmesg | tail -12
- [51329.226687] mmc0: card aaaa removed
- [51776.154562] mmc0: new high speed SDHC card at address aaaa
- [51776.154894] mmcblk0: mmc0:aaaa SL16G 14.8 GiB
- [51776.169240] mmcblk0: p1 p2 < > p3
- [51781.342106] EXT4-fs (mmcblk0p3): mounted filesystem with ordered data mode. Opts: (null)
- [51791.757878] mmc0: card aaaa removed
- [51791.773880] JBD2: Error -5 detected when updating journal superblock for mmcblk0p3-8.
- [51793.651277] mmc0: new high speed SDHC card at address aaaa
- [51793.651601] mmcblk0: mmc0:aaaa SL16G 14.8 GiB
- [51793.666335] mmcblk0: p1 p2 < > p3
- [51799.516813] EXT4-fs (mmcblk0p3): recovery complete
- [51799.518183] EXT4-fs (mmcblk0p3): mounted filesystem with ordered data mode. Opts: (null)
-
- (The "Error -5 detected bit.)
-
- Ok, so I bought a new Sandisk-branded card because I didn't have a decently
- fast microSD card laying around. What I'm going to check before I go any
- further is whether I got one the Pi can't deal with. (Or just one that's bunk.
- I bought this thing for 15 bucks at Best Buy, so who knows.)
-
- Here's an 8 gig class 4 card, branded Kingston, but I probably got it off the
- shelves at SparkFun some time in the last 3 years, so its actual provenance is
- anybody's guess. Looking at what's on here, I've already used it for a
- Raspberry Pi of some flavor in the past. Let's see if it'll boot as-is.
-
- Ok, no dice. I'm starting to suspect my problem lies elsewhere, but I'll try
- one more time on this card with NOOBS.
-
- Again: No dice.
-
- Also checked:
-
- - the monitor with other inputs, because who knows
- - tried a couple of different power supplies - USB cable from my laptop, 5V
- wall wart purchased from SFE, cell phone charger.
- - the usual plug-things-in-one-at-a-time routine.
-
- -> ✦ <-
-
- Time to try one of these cards with an older RasPi, if I can figure out where I
- put any of them.
-
- After much shuffling through stuff on my dining room table / workbench, I find
- a model B. It fails in much the same way, which leads me to suspect again that
- I'm doing something wrong with the card, but then I can't quite remember if
- this one still worked the last time I plugged it in. They can be fragile
- little critters.
-
- Here's a thought, using a Raspbian image I grabbed much earlier this year:
-
- brennen@desiderata 17:10:03 /home/brennen/isos ★ sudo dd if=/home/brennen/isos/2014-01-07-wheezy-raspbian.img of=/dev/mmcblk0
-
- No dice on either the model B or model B+, using the new SanDisk.
-
- Trying with the older card, `dd` spins through 800ish megs before giving me an I/O error.
-
- It may be time to start drinking.
-
- -> ✦ <-
-
- The next day: I swing through a couple of stores in town with the [wiki list
- of known cards in hand](http://www.raspberrypi.org/forums/viewtopic.php?t=58151) and buy a pile
- of cards across a handful of brands, plus a $20 card reader (the Insignia
- NS-CR20A1) since there's not one built in to the laptop I'm carrying today.
- The first card I try boots NOOBS instantly; an installer is running as I type
- this.
-
- Suddenly It occurs to me that the card reader on the laptop I was using last
- night might is likely dying/dead.
-
- This is a really slick install process now, so good work to somebody on that.
-
- beaglebone black
- ----------------
-
- I've got a Beaglebone Black sitting here new in the box. It comes with a USB
- cable, so I plug it in. Instantly there are bright blue blinky lights, and my
- laptop tells me I'm connected to an ethernet network and I've got a new drive
- mounted with some README files in it.
-
- This is kind of great.
-
- Browsing to to 192.168.7.2 gets a bunch of docs and a link to Cloud9, an
- in-browser IDE that happens to include a root terminal.
-
- I don't really know what's going on here. I think it might be a little
- scattered and confused as a user experience, in some ways. But it immediately
- strikes me as good tech in a bunch of ways.
-
- Josh Datko, who I've gotten to know a little bit, has a book called _Beaglebone
- for Secret Agents_. It's been on my ever-growing to-read list for a while; I'm
- going to have to give it a look sooner rather than later.
- reading list
- ------------
-
- * http://www.jann.cc/2013/01/15/trying_out_the_adafruit_webide.html
- * http://www.angstrom-distribution.org/
- * http://www.raspberrypi.org/documentation/configuration/config-txt.md
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