Create NDIF disk image from RasPi SD card

Hello Jan,
JP> Do not move the goal posts.
Sorry but you did. We are talking about both read and write speeds. They both matter when making backups and copies.
JP> First, to MAKE a backup you need to read the card.
Yes and second you have to write to another device, mostly an SDcard, not device Zero ;-).
JP> That read happens (if things are done right) much more often than a JP> 'restore'
May be at your site, but not here.
JP> where you write the backup back to the card.. JP> The restore may even never happen if things are done right.
For your own operated cards yes. But I am creating SDcards for skippers who buy a Raspberry Pi 3B(+) for AIS+ECDIS inland navigation, so for me the write time used counts very much too! In that way the right command used is essential.
JP> On the write timing issue, it will very likely just be limited by he JP> specified card write speed, JP> if it is a half way decent card it will take care of the allocation.
As I showed this day with the 32 GB copying, the right commands counts very much.
JP> Well, I recently bought let me see, JP> MB-MC32DA/EU Samsung Evo+ 32 GB Micro SD class 10 met adapter JP> That was in March, is used in my drone, and in my video camera. JP> read speed up to 80 MB/sec. JP> write speed up top 20 MB/sec.. JP> UHS-I-speed class 1 (U1), class 10 JP>
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JP> sd-adapter/MB-MC32DAEU/ JP> Best ones I could find.
I think my Kingston 16, 32 and 64 GB versions have the same specifications. I paid E.7.95, E.9,95 and E.19,95 for them. So the 16 GB one is relatively more expensive than the 32 and 64 GB ones.
formatting link
in Doorwerth.Gld.NL.
JP> I have some older 8 GB and 16 GB cards in the raspis, JP> but I am sure as I just went for the best in those days JP> that those have a decent control chip.
Some friends of my lost cards by using thim intensively. The answer is to not fill them up for more than 50%. That way the card software can level the wear better. Make a ramdisc and use that for scrap, as I did for RISC OS at the Pi. I now have to figure out how to make a ramdisc under Raspbian Stretch Linux, and move the scrapfiles to after booting, for less wear. Electronic storage at SDcards, USBsticks and SSD HDD's have shorter lifetimes than magnetic media had, so beware.
JP> Also have a bunch (from ebay) 2 GB cards for things that do not JP> support > 2 GB, or do not need that and the speed, JP> such as auto-pilot drone: JP>
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JP> old WiFi webserver, etc.
The only apparatus with a 2 GB limit are my Acorn RiscPC and the Aldi Traveler DC8600 still photocamera.
JP> And of course I wrote the software to read / write to some of those JP> cards myself in asm actually JP> All sector based... :-)
Assembler was a bridge to far for me.
JP> You can use hdparm to get some info on the cards you have. JP> Not sure you can still get older cards, the old 2 GB ones I got from JP> ebay ware almost more expensive JP> than the new fast ones.. getting rare for people who do not want to dump JP> old equipment, sellers can ask what they want, like for antiques :-)
I remarked the same attitude. So I gathered some old 2GB cards from friends who didnot use them anymore. I takes more tha a year to fill up the 2 GB card with the photocamera. I made more than 6600 photo's since 2006, and I am using now the 7th SDcard in that camera.
JP> But next time I need to write back a raspi backup image (hope it never JP> happens) I will show the write timings with - and without bs=1M.
W'll see that in future I hope.
Henri.
Reply to
Henri Derksen
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On Tue, 24 Jul 2018 14:07:00 +1200, snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) declaimed the following:
There is one already -- though I forget if it is /dev/shm or /run/shm [the R-Pi and the Beaglebone use different names].
--
	Wulfraed                 Dennis Lee Bieber         AF6VN 
	wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/
Reply to
Dennis Lee Bieber
Doesn?t matter on Raspbian, one is an alias for the other.
Reply to
A. Dumas
What do you mean by 'read'? Do you mean using dd to /dev/null, or using dd to copy it on the card the machine has booted from? I'd be very surprised if the former failed, and you should not be doing the latter, as writing to a running image will cause it to be corrupted.
When copying between cards, it is common to find that no two of the same stated capacity have exactly the same number of sectors, and you can't perform an exact copy from a larger card to a smaller one.
To get around this, after setting up an Pi image and allowing it to expand to the size of the card, I then remove it and use gparted to shrink the last partition by 1M. This means it can safely be copied to a slightly smaller card without losing anything vital. Note this may not be possible with the NOOBs card layout, which is why I avoid it.
---druck
Reply to
druck
On a sunny day (Tue, 24 Jul 2018 13:59:00 +1200) it happened snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) wrote in :
mm You are copying on a raspi??? Using external card reader with 2 slots? What is your hardware setup?
I copy as folows. power off raspi take card out put it in laptop copy to /dev/zero (for demo card speed) that is always about the same as what hdparm -t /dev/card says, no matter what blocksize. At least on my 8GB card.
If you copy to a file on harddisk, say some.img then you also need to look at how fast that harddisk goes sector by sector. USB card readers may do things to speed, especially old ones, if you saturate the USB2...?
Here some test on my laptop with ever increasing filesize, card in /dev/sdc hardisk partition is /dev/sda5 destination file q1 card is latest 32 GB Samsung cllass 10 or sometging that I mentioned in this thread before. do not have more free space ATM, but no real differences:
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=1 bs=1M 1+0 records in 1+0 records out 1048576 bytes (1.0 MB) copied, 0.0687257 s, 15.3 MB/s
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=2048 2048+0 records in 2048+0 records out 1048576 bytes (1.0 MB) copied, 0.080926 s, 13.0 MB/s
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=10 bs=1M 10+0 records in 10+0 records out 10485760 bytes (10 MB) copied, 0.622834 s, 16.8 MB/s
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=20480 20480+0 records in 20480+0 records out 10485760 bytes (10 MB) copied, 0.6317 s, 16.6 MB/s
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=100 bs=1M 100+0 records in 100+0 records out 104857600 bytes (105 MB) copied, 6.85355 s, 15.3 MB/s
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=204800 204800+0 records in 204800+0 records out 104857600 bytes (105 MB) copied, 6.79278 s, 15.4 MB/s dd if=/dev/sdc of=/mnt/sda5/q1 count=1000 bs=1M 0.01s user 5.44s system 6% cpu 1:18.03 total
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=2048000 2048000+0 records in 2048000+0 records out 1048576000 bytes (1.0 GB) copied, 68.2988 s, 15.4 MB/s dd if=/dev/sdc of=/mnt/sda5/q1 count=2048000 0.58s user 9.93s system 15% cpu 1:08.57 total
~ # dd if=/dev/sdc of=/mnt/sda5/q1 count=1000 bs=1M 1000+0 records in 1000+0 records out 1048576000 bytes (1.0 GB) copied, 69.051 s, 15.2 MB/s
The card read speed: # hdparm -t /dev/sdc
/dev/sdc: Timing buffered disk reads: 46 MB in 3.10 seconds = 14.82 MB/sec panteltje10: /mnt/sda5 # hdparm -t /dev/sdc
/dev/sdc: Timing buffered disk reads: 46 MB in 3.10 seconds = 14.83 MB/sec
The harddisk read speed: # hdparm -t /dev/sda
/dev/sda: Timing buffered disk reads: 338 MB in 3.00 seconds = 112.64 MB/sec panteltje10: /mnt/sda5 # hdparm -t /dev/sda
/dev/sda: Timing buffered disk reads: 370 MB in 3.01 seconds = 123.02 MB/sec
So, I do not know what all your problems are, but this is get back to basics...
Of course you should not do the copy on a rapi itself, it is not a real computah ;-) ;-) ;-)
And it is just data, sector by sector, does not matter what is on it.
Reply to
Jan Panteltje
Hello David,
I mean mounting them.
DR> What do you mean by 'read'?
I wanted to mount the new card after making a backup on it, and that failed because it has the same UUID as the one booted from ;-(.
No, not at all.
No, I never did that.
Yes, but i did not even tried that. The new card is ok, and you can read it with dd, but you can NOT mount it any more if it is a 100 % backup from a Raspbian Stretch Linux you booted from. Does not matter you made that backup with the Raspbian util SDCard copier, or using dd with one or two card reader/writers from the local /dev/mmcblk0. With the SDcard copier you now have the option at Stretch to change the UUID during copying from the internal microSDcard you booted from, i.e. /dev/mmcblk0 to a card (same make, type and capacity) via a sdcard reader/writer at the destination: /dev/sda or /dev/sdb etc.
Yes I knew and never did. With the Raspbian SDCard Copier from the Accessoires menu that is impossable.
I know for many years. That often happened when using different makes and/or types, but I seldom do that.
I know this tric and I sometimes did. But nowadays I allways use the same make, type and capacity of microSDcards.
I know. It has a different layout at the end of the card.
Sorry, but I hate NOOBS for more reasons ;-(. I never use it anymore, I only did:
pi@raspberrypi:~ $ sudo dd if=/dev/sda of=/dev/sdb bs=1M
at a Pi3B booted from a Raspbian Jessie Linux, but the card on /dev/sda is a Raspbian Stretch Linux. When booting from that new Stretch Linux, i.e. in the internal card slot: /dev/mmcblk0 I can NOT mount the backup in a cardreader made from that same Raspbian Stretch Linux, because it has the same UUID as the booted one ;-(. That's now the new problem there never was before Stretch, i.e. with Jessie, and I donot understand why the Stretch developers made that differend UUID decision? So now my solution is to made two Stretch versions; one at a 16 GB card, and one at a 32 GB card, so they are different. Or mount the Stretch crad from a Pi booted from Jessie.
From the help of de SDcard copier util:
" Under Raspbian Stretch and later versions, you cannot mount two partition, with the same UUID, so you will not be able to mount a cloned SD card when booted from the disk from which it was cloned. If you need to do this, check the "New Partition UUIDs" box before copying. "
When backing up using the Raspbian SDcard copier I remarked that the copy had less free space than the original card from the same make, type and capacity. I donot understand why? I only use Kingston microSDcards. When I made the backup using dd with two card readers/writers, the free space is the same at both cards, but then you have also the same UUID's, wich is a conflict when you want to mount them.
Is there a utility to change the UUID on a backed up card afterwards? Or is that only possible when making a backup with the Raspbian SDCard Copier?
Henri.
Reply to
Henri Derksen
Hello Jan,
JP> You are copying on a raspi???
Yes, why not, I do not have another Linux machine.
JP> Using external card reader with 2 slots?
External card reader yes, but NOT using the 2 slots at the same time. The source is the internal SDcard slot: /dev/mmcblk0 The destination is /dev/sda
JP> What is your hardware setup?
Raspberry Pi, 1B, 1B+, 2B, 3B and 3B+, Logitech wireless keyboard and mouse using a 2.4 GHz USB2A dongle, DVI-D monitor, and one or two SDcardReaders/writers booted from the latest Raspbian Stretch 2018-06-27 and of course updated and upgraded at 2018-07-22.
JP> I copy as folows. JP> power off raspi JP> take card out JP> put it in laptop
I donot have a laptop with Unix/Linux. but only a Win2K one, or a desktop with Win XP I hardly use. But I can boot from a Lubuntu 14.04 CD.
JP> copy to /dev/zero (for demo card speed)
Why should I do that? It only takes my valuable time ;-(.
JP> that is always about the same as what hdparm -t /dev/card says,
Raspbian does not know that command: hdparm.
JP> no matter what blocksize. JP> At least on my 8GB card.
You have Raspbian Stretch Linux from 2018?
JP> If you copy to a file on harddisk, say some.img JP> then you also need to look at how fast that harddisk goes sector by JP> sector. JP> USB card readers may do things to speed, especially old ones, JP> if you saturate the USB2...?
I see.
JP> Here some test on my laptop with ever increasing filesize, JP> card in /dev/sdc hardisk partition is /dev/sda5 destination file q1 JP> card is latest 32 GB Samsung cllass 10 or sometging that I mentioned in JP> this thread before. JP> do not have more free space ATM, but no real differences:
My problem is the new Raspbian Stretch UUIDs !
JP> So, I do not know what all your problems are, but this is get back to JP> basics...
That only happens when I am backing up between two differend speeds SDCards. I mostly use the same make, type, speed and capacity cards.
JP> Of course you should not do the copy on a rapi itself, it is not a real JP> computah ;-) ;-) ;-)
Besides my old M$ DOS BBS PC and Acorn RiscPC at RISC OS 4.04, I do not have anything else than the menioned 5 Pi's, Win2K laptop and a Win XP desktop.
JP> And it is just data, sector by sector, does not matter what is on it.
For copying yes, but for mounting, it makes a huge difference. You can not mount SDcards anymore with the same UUID as the booted one since Raspbian Stretch Linux, witch is a quirc from March 2018. And I still do not know why they made that impossable. With the older Raspbian Jessie or Wheezy mounting a 100 % backup card was no problem at all.
Henri.
Reply to
Henri Derksen
Hello,
That may be, but I still do not know how to make a ram drive at starting up, and change the scratch from the SDcard to the ramdrive? I want to lower the amount of wear.
Henri.
Reply to
Henri Derksen
$apropos UUID dbus-uuidgen (1) - Utility to generate UUIDs findfs (8) - find a filesystem by label or UUID swaplabel (8) - print or change the label or UUID of a swap area UUID (3pm) - Perl extension for using UUID interfaces as defined in e2fsprogs. uuidd (8) - UUID generation daemon uuidgen (1) - create a new UUID value
Reply to
Andreas Neumann
Is your web search broken?
"create ram disk linux"
Reply to
Andreas Neumann
On a sunny day (Mon, 30 Jul 2018 20:07:00 +1200) it happened snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) wrote in :
OK, to make a long story short:
Do Not Do That
When you make copy from a running system to an other card, then the source changes while the copy is being made.
Links may be changed, log files may be appended, or created, data may be changed.
So the new copy will likely not run, and even if it does it WILL contain errors and inconsistencies.
The right way is stop the raspi (type poweroff in a terminal perhaps) and do the copy on an other system.
Reply to
Jan Panteltje
PS what you perhaps 'could' do, if all you have is 1 raspi and 1 card reader, is boot from some other HUGE[1] SDcard.
Take the original card and put it in the card reader copy it to file with dd dd if=/dev/cardreder of=image1.img
Now you have the backup.
You could then also copy back to some other card, put new card in cardreader dd if=image1.img of=/dev/cardreader
All as root, use sudo if you have root fear.
[1] must have enough space for the OS and apps and the image.
Having a PC or laptop with large hardisk, could not do a thing without. Important backups also go to bluray here.
So FLASH, magnetic, AND optical. AND I have some MDISKs, supposed to last a century.
Reality rules, if there was a simpler way I'd use it. Greetings Jan
Reply to
Jan Panteltje
It already is a disk (well, a mount point), you can write to and read from it. By "the scratch", do you mean the swap space? You could move the swap there (Raspbian uses a swap file not swap partition, see /etc/fstab), which I guess is possible if you have enough free memory. Test how much memory you have with "free". Swap file configuration is in /etc/dphys-swapfile. Of course that is completely self-defeating: swap space gets used only when you're out of memory...
What you want is to make use of
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e.g. as in
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Reply to
A. Dumas
Hello Andres,
HD>> That may be, but I still do not know how to make a ram drive at starting HD>> up
AN> Is your web search broken?
Yes, when I am sailing on an old inland cargo sailing ship with only a Raspberry Pi 2B which has no InterNet connection and no WiFi ;-(. Ofcourse at home I have all the resources I needed.
AN> "create ram disk linux"
Ofcourse I can do that, but why use the difficult way of finding out the wheel again, if someone else know the exact trics already and even can place a batch file here ;-).
And second, at Rasbian and the Pi things often work different, or even not at all ;-(. That's why we have this conference ;-).
At home I can use DPMS at most machines, until somebody told me the Pi's donot have the hardware to let go the monitor in low power mode. I nowhere could find the reason why, until I asked someone at the computer clubs I frequently visit, 7 in the Netherlands and one in Belgium.
Some guy at the computer club told me many times: Asking you is much faster, than finding out myself. That's the result of having a reputation of knowing much, but I am also a nitwit at new fields like Linux is for me. No one knows everything, even Google does not.
Henri.
Reply to
Henri Derksen
Hello Jan,
JP>>> Using external card reader with 2 slots?
HD>> External card reader yes, but NOT using the 2 slots at the same time. HD>> The source is the internal SDcard slot: /dev/mmcblk0 HD>> The destination is /dev/sda
JP> OK, to make a long story short: JP> Do Not Do That
JP> When you make copy from a running system to an other card, JP> then the source changes while the copy is being made.
Yes I know, but in this case, it does not matter.
JP> Links may be changed, log files may be appended, or created, JP> data may be changed.
If you use the machine intensively, yes.
JP> So the new copy will likely not run, and even if it does it WILL contain JP> errors and inconsistencies.
Not if you donot use the machine during copying.
JP> The right way is stop the raspi (type poweroff in a terminal perhaps) JP> and do the copy on an other system.
Last time I was on a ship with a Pi 2B, only one cardreader and nothing else. There were no other machines. He was running a corrupted backup from a card his nephew made for him. Some people donot shut down the Pi after use ;-(. I only had one new fresh filled card with me, and he had another card (same type) I made for him in march 2018. So I put my new card in the internal slot, and his card from March 2018 in the cardreader and we made the backup with the internal SDcard copier program. This way we always had a working card (from his nephew) if things went wrong. During the backup we did nothing with the machine and it took 90 minutes to complete the backup. A long time compared to the 28 minutes I got at my Pi 3B+ with two cardreaders and dd with 1M blocks. I did not expect a three times longer backup time at a Pi 2B versus a 3B+ But afterwards the new copy worked much better than the crappy backup did.
When sailing and traveling with my foldable bike, I do not have enough room to transport a large amount of computer hardware. So next time I have to take 2 cardreaders with me, and leave that clean underware out of my case ;-). I did not use it anyway this time. But if I take two cardreaders with me, you should see I only need one, and because of an accident (bad meal), I do not have clean underware. So it is always trouble to pack the right things when traveling ;-).
Henri.
Reply to
Henri Derksen
Hello David,
DR>>> When copying between cards, it is common to find that no two of the same DR>>> stated capacity have exactly the same number of sectors, and you can't DR>>> perform an exact copy from a larger card to a smaller one.
HD>> I know for many years. HD>> That often happened when using different makes and/or types, HD>> but I seldom do that.
DR>>> To get around this, after setting up an Pi image and allowing it to DR>>> expand to the size of the card, I then remove it and use gparted to DR>>> shrink the last partition by 1M. This means it can safely be copied to a DR>>> slightly smaller card without losing anything vital.
HD>> I know this tric and I sometimes did. HD>> But nowadays I allways use the same make, type and capacity of HD>> microSDcards.
In my archives I found this:
7.969.177.600 Bytes at Kingston 8 GB C10 1st Fat partition is 56 MB 2nd EXT partition is rest According RISC OS !CloneDisc 7.421 GiB 15.564.800 sectors
Kingston 8 GB C4 Accordimg RISC OS !CloneDisc 7.318 GiB 15.347.712 sectors
Intenso 8 GB C4 7.746.879.488 Bytes write According RISC OS !CloneDisc 7.214 GiB 15.130.624 sectors
So the differences are very much more then your mentioned 1 MB ;-(. That's why I always buy the same make, type and capacity Kingston microSDcards from the same supplier, a shop 10 km from here, and mostly four at a time. I often need them to create an AIS+ECDIS system with Rasbian Linux + OpenCPN ECDIS-viewer and most European governmental S57 inland waterway charts and also the OpenSeaMap charts from .NL and .BE for the smaller canals, rivers and lakes to support the skippers of old recreational ships, former cargo ships and old tugs etc. See . The Netherlands has the largest collection of historical ships in the world. At that website there is also a chapter about AIS+ECDIS. I am one of the members of that club, and made OpenCPN ECDIS viewer work under Raspbian Wheezy on the Pi 1B in december 2014 for our skippers. I am now with version 5 of the 16 GB SDcard using Raspbian Stretch, and just compiled OpenCPN 4.99.0 to it, together wich many inland ECDIS charts of Western Europe. That S57 + OSM charts alone take 3.4 GB ! It consists of maps from The Netherlands, Belgium, France, Germany, Switserland, Austria and Poland. But there are more if you wisch to install, i.e. south east Europ countries. I did not research if there are inland water charts for England, Norway and Sweden? So there is very much to sail to and on. Good luck in copying (micro-)SDcards.
Henri.
Reply to
Henri Derksen
Hello Jan,
JP> PS what you perhaps 'could' do, if all you have is 1 raspi and 1 card JP> reader, is boot from some other HUGE[1] SDcard.
The HUGE is the problem. Until now I only buy the capacity I need, nothing more.
JP> Take the original card and put it in the card reader JP> copy it to file with dd JP> dd if=/dev/cardreder of=image1.img
That will take a very long time with no 1M blocks ;-(. And it will go much faster with 2 identical SDcard reader/writers.
Another solution could be to reduce the image by compression, i.e. on the fly making them, or afterwards. Some guy told here how to do it on the fly when making the backup. I can look up how if you want to know how, or read back yourself.
JP> Now you have the backup.
In stead of a HUGE internal SDcard, a USB stick or HDD is a much better solution. I do not know the lifetime of a SSD? But to keep that as long as possible, reduce the amount of writings, and do not fill it up for more than 50 %. The you have the less wear and the longest lifetime.
JP> You could then also copy back to some other card, JP> put new card in cardreader JP> dd if=image1.img of=/dev/cardreader
Again the 1M block size is missing ;-(.
JP> All as root, use sudo if you have root fear.
I know. The first thing I do after installing a new Raspbian Linux, is to change the default is your fault password. And of course I write that down somewhere save, my skippers also know. Only after that you can swith on SSH safely, but I never used that.
JP> [1] must have enough space for the OS and apps and the image.
Making backups on the same media you are using for production is never a good idea, if you have no other places to store also ;-(. The SDcards from my camera are never overwritten and copied to external HD's. When coming home after a trip, I often copy the latest photo's to at least the external USB HDD. When the sdCards are full, they are all stored as my original unaltered "negatives". So I have at least 3 copies of my digital photo's; The original sdCard, 2 external HDD's and mostly also at a USB stick, especially the nautical ones about locks an ships, I use much.
JP> Having a PC or laptop with large hardisk, could not do a thing without. JP> Important backups also go to bluray here.
I donot have BlueRay. Store on several external magnetic HDD's is a better way, especial when you store vital information also outdoor at family or friends. CD-drives are often killed by heat ;-(.
JP> So FLASH, magnetic, AND optical.
Yes, that's the right way. But do some ways double and/or external, i.e. at work or family.
JP> AND I have some MDISKs, supposed to last a century.
What's that MDISKs?
JP> Reality rules,
I know.
JP> if there was a simpler way I'd use it. JP> Greetings
same to you. Henri.
Reply to
Henri Derksen
On a sunny day (Wed, 01 Aug 2018 09:53:00 +1200) it happened snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) wrote in :
Yes, that is complicated, you could go naked though, only wear a backpack. You did say 'you do not use machine during copying' Linux is very much alive, it is doing things all the time, type ps avx to see some processes. or type top
That sort of fiddling is not a chance I want to take, but maybe for an emergency copy.. The other problem you then have is that you cannot run a verify. diff myimage /dev/sd? I wrote a special program for that to compare dvd and bluray images, but it will compare anything:
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dvdimagecmp -a /dev/sd? -b myimage.iso should work Every disk burn here is compared with it, it gives relative speed compared to CDs and reports sectors that differ too.
Anyways, for 'on the road' (or in a train) I have a small Asus eeepc that runs Linux with a Huawei 3G USB stick to connect to the net, takes hardly any space, and has a real keyboard. Usually I just ssh -Y to my home LAN with it, and nobody could tell I was not there.
Greetings Jan
Reply to
Jan Panteltje
On a sunny day (Wed, 01 Aug 2018 13:42:00 +1200) it happened snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) wrote in :
Dutch:
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English:
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Greetings Jan
Reply to
Jan Panteltje
On Wed, 01 Aug 2018 09:53:00 +1200, snipped-for-privacy@f1208.n80.z2.binkp.net (Henri Derksen) declaimed the following:
I have a uSD card reader that is about the size of a large Chiclet gum. Or, to put it in terms of something readily available, the size of the standard USB /connector/ shell with a small bit of plastic on the exposed end -- with a slot for the uSD card. If you've got room for a pair of dice, you've got room for 4-6 of these readers.
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--
	Wulfraed                 Dennis Lee Bieber         AF6VN 
	wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/
Reply to
Dennis Lee Bieber

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