January 2020 - main

How to get the MAC address of the 'local' system given the IP address?
by Chris Green 31 Jan '20

31 Jan '20

You'd think this was easy but although I can find the information easily enough I can't find a concise way of doing it. What I want is to get same information for the system I'm logged into as is given by 'arp-scan -lx' for all other systems on the LAN:- root@t470:~# arp-scan -lx 192.168.1.1 xx:xx:xx:xx:xx:xx DrayTek Corp. 192.168.1.3 xx:xx:xx:xx:xx:xx Fujitsu Technology Solutions GmbH 192.168.1.4 xx:xx:xx:xx:xx:xx Raspberry Pi Foundation 192.168.1.10 xx:xx:xx:xx:xx:xx TP-LINK TECHNOLOGIES CO.,LTD. 192.168.1.20 xx:xx:xx:xx:xx:xx DrayTek Corp. 192.168.1.50 xx:xx:xx:xx:xx:xx Oki Electric Industry Co., Ltd. 192.168.1.96 xx:xx:xx:xx:xx:xx HUMAX Co., Ltd. 192.168.1.98 xx:xx:xx:xx:xx:xx TP-LINK TECHNOLOGIES CO.,LTD. 192.168.1.111 xx:xx:xx:xx:xx:xx TP-LINK TECHNOLOGIES CO.,LTD. 192.168.1.114 xx:xx:xx:xx:xx:xx MICRO-STAR INT'L CO.,LTD 192.168.1.95 xx:xx:xx:xx:xx:xx Sonos, Inc. 192.168.1.104 xx:xx:xx:xx:xx:xx Amazon Technologies Inc. I can get IP address of my current LAN connection using 'hostname -i':- chris$ hostname -i 192.168.1.92 ... but I can't find a neat way of getting the corresponding MAC address and company information as for arp-scan. The MAC address can be obtained using ifconfig or ip but it's an exercise in frustration trying to extract the relevant bits:- chris$ ifconfig enp0s31f6: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 ether c8:5b:76:de:2a:fc txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 device interrupt 16 memory 0xec200000-ec220000 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1000 (Local Loopback) RX packets 639 bytes 279749 (279.7 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 639 bytes 279749 (279.7 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 wlp4s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.92 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::8239:9067:e11:92be prefixlen 64 scopeid 0x20<link> ether xx:xx:xx:xx:xx:xx txqueuelen 1000 (Ethernet) RX packets 14315 bytes 7281010 (7.2 MB) RX errors 0 dropped 1 overruns 0 frame 0 TX packets 14719 bytes 1911802 (1.9 MB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 You'd have to first find that the WiFi device wlp4s0 is providing the LAN interface (I want it to work when it's wired with enp0s31f6 when that's in use, can't just hard code wlp4s0) and then go to the 'ether' line to get the MAC address. Even then you don't get the company name. It's possible but hard work and messy, I'd like to find a simple way. -- Chris Green

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VPN question, or how to get a single WiFi device to seem to be in the UK
by Chris Green 29 Jan '20

29 Jan '20

I have a Kobo eReader which connects to a local network by WiFi. It uses the connection to download books (surprise) and also to do other things with my library on-line account. All very well when I'm in the UK but for (stupid?) reasons known only to themselves the Kobo/Overdrive/Library software and connections work only when the Kobo is connected to a UK IP address. So, when I'm trotting around the world, or more likely when I'm sitting in my little boat in France, I can't get the Kobo to update even though I have books available at the library. What makes it even sillier is that I *can* read the books on my laptop, even when connected from France, so it's not an issue about "you can't read that book in France" it's just a quirk of the eReader software. Anyway, down to the question, what's the simplest way to get a connection to the eReader such that the library/Overdrive software will think it's in the UK? I can see that it *could* be done with two VPN aware routers, one in the UK (I have Drayteks at home which can do VPN) and one here on the boat. However that does seem a rather heavyweight solution just to connect a single WiFi device. (and I don't have a VPN capable router here at the moment though in the longer term I could bring one out) Is there any other way of doing it (VPN or not, ssh maybe)? I already use an ssh proxy occasionally to allow my laptop to seem to be in the UK so I can connect to my NHS Doctor site (silly restriction again!). However I can't do this (so easily) with the eReader because it's basically a 'closed' system with just the eReader software in it. Any bright ideas anyone? -- Chris Green

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Mint Cinnamon
by Phil Thane 22 Jan '20

22 Jan '20

Hello Is anyone else using Linux Mint 19.3 with Cinnamon desktop? I've found a bug I think. I'm in the habit of hitting [Alt][F2] to bring up a simple CLI application starter. On previous desktops (and Mint 19.2 I think) there's an autocomplete function and if you mistype you get an error message. On the current version bringing up the app starter greys out the rest of the screen and if you type correctly the full name and hit [Enter] it works OK. There's no autocomplete though and if you mistype and hit [Enter] then the dialog box freezes, the screen stays mostly grey and the panel stops working. The only way out as far as I can see is to logout or reboot. Fortunately the keyboard/mouse still work so you can bring up the menu with the 'winkey' and log out from there. I've tried PS UX in a terminal to try to find the process and kill it but there's nothing obvious there. I've tried Googling* without success. Any suggestions? Worth signing up to the Mint forums? PINEBOOK PRO UPDATE It's working fine, since updates Firefox is more stable so I've set that as default instead of Chromium. There's a dearth of browser plugins, I guess they have to be recompiled for ARM. I use ad blockers and tracker blockers normally plus 'copy plain text' but none of them are available. You Tube plays fine, sound is as you'd expect from tiny built-in speakers, OK for speech, terrible for music. I have a slightly odd use-case in that I have a canal/river cruiser and take long trips in the summer. Last year I installed a 12V radio/amp in the boat and ran my old laptop audio through that, I plan to do the same with the Pinebook Pro but haven't tried it yet. Unlike some trendier devices it still has a conventional 3mm audio-out socket. Libre Office and Gimp work OK except none of the GEGL operations seem to work in GIMP. They are a bit half-assed in the AMD64 version anyway so until it becomes mainstream you're not missing much. New themes are a bit of a lottery but the default appearance isn't bad and I've tweaked it a bit. The trackpad is much better since the firmware upgrade but I'd still like a wider target area on the window corners/edges to resize things. Mind you that's an issue on my Mint desktop too. Dodgy old eyesight and shaky hands probably don't help. Just read a review of a new KDE laptop. Higher spec than PinebookPro (Intel i7) but literally 10x the price. * Not Google I use Start Page but Googling seems to have become a verb. -- Phil Thane www.pthane.co.uk Tweet @pthane 01767 449759 07582 750607

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Advice please
by Michael Goddard 20 Jan '20

20 Jan '20

I use Mint Cinnamon 19.3 and whilst trying to use kernel update, I caused the following msg. "You have 3 broken packages on your system. Use the 'Broken' filter to locate them." Somewhat beyond my limited Linux experience. Any advice on next step, or should I just ignore this kernel update, would be much appreciated. Tia Michael

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Pinebook Pro
by Phil Thane 17 Jan '20

17 Jan '20

Hello Lugs, Xmas present to self was a PinebookPro <https://www.pine64.org/pinebook-pro/> Mostly I'm pleased with it but found two problems with no solutions on Pine forums (perils of being an early adopter). 1. This is an issue on my Mint Desktop too, and my wife's KDE Neon. Is there a way to make window borders wider? Or if not visually larger then make the target area bigger? When trying to manually resize a window I find it very hard with mouse or trackpad to hit the edge/corner to click and drag. Slim borders look great but don't work well (for me). 2. Specifically Pine but shows how much I don't understand... We have a laser printer connected by USB to my wife's PC (as she prints most) but 'shared' so I can print via ethernet from my desktop. My Mint PC found the share and set it up easily. The PinebookPro also finds it, but set up doesn't work. First, there's no Printer utility so I installed CUPS via Synaptic, then accessed it via localhost:631 in Chromium. Doesn't work so tried re-launching Chromium as root from terminal. That gets me into CUPS OK. It detects the shared printer OK but doesn't list the maker (Samsung). I guess that's because Samsung haven't released an ARM driver. I've never really understood why you need a locally installed driver anyway to use a printer installed on another PC (does anyone?) CUPS has an alternative for unlisted printers though, install a PPD file. So I downloaded it from Samsung and installed it. All the set up seems to go OK after that but trying to print just throws an error 'Unable to locate printer' which is weird because the setup DID locate it. Some interesting extras to this. Our router has a USB port that can be used with either NAS or shared printers. I tried that in the past and couldn't make it work at all. Someone suggested that the printer might request firmware from the PC and maybe the router doesn't understand the request. Whatever that's no help. The printer has an ethernet socket so could be a network printer, but the router has only 4 sockets and they are all occupied (server, smart TV, 2 desktops). Short of buying a switch that's out too. The printer also has WiFi which the network setting widget on the Pinebook finds automatically. It asks for a password which Samsung don't supply, they tell you to use the (Windows/OSX) set up CD! Any suggestions? It'd be nice to print, but not essential I can always print to file and email it to myself! -- Phil Thane www.pthane.co.uk Tweet @pthane 01767 449759 07582 750607

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A mostly 'just thinking aloud' question about web security etc.
by Chris Green 12 Jan '20

12 Jan '20

I have been looking at making some web pages of mine *slightly* more private recently. There's nothing seriously important on them, just some addresses (that people could find elsewhere easily enough) and some other similar sorts of bits and pieces. However, while I was doing this, I wondered about the "passwords are in clear when using HTTP" thing. If I go to my web site 'out there' and type in a password who/what/where/how will it be seen? Yes, I realise if someone has wireshark running on my LAN they will be able to see it (but my house is reasonably secure!) and, presumably, anyone monitoring packets whizzing around between me and the remote site would be able to see it. However there's a *lot* of packets flying around out there, how would anyone pick out any relevant bits? The remote end is 'mine' too in that it's a virtual server in France (Gandi Internet) so that is moderately secure too with no general access. Obviously anyone with access to the systems at either end of this transaction could see what's going on but then if they have that sort of access getting at a web page password is not going to get them any more access than they have already. This isn't bank access or accessing a big business/selling web site where snoopers might expect to get useful/valuable information so why (and how) would any sort of snooping work? What does the team think? Am I being too un-paranoid? (N.B. the passwords I use for moderately [in]secure web sites bear no relation to the ones I use for secure stuff) -- Chris Green

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[ALUG Announce] ALUG Norwich Pub Meet Thursday 9th January
by Viperfang 06 Jan '20

06 Jan '20

ALUG Announce Please send announcements to Announce(a)lists.alug.org.uk Unsub, change settings via https://lists.alug.org.uk/mailman/listinfo/announce ----- Hello Norwich Aluggers, Our monthly ALUG Norwich social meeting will be held this Thursday, 9th January at The Coach and Horses (82 Thorpe Road, Norwich, NR1 1BA). The meeting officially starts at 8pm, although some people may arrive earlier. More information on those people can be found on the list and the IRC channel. If you are unsure if you will recognise us then make yourself and your intent to attend known by either posting on list or visiting us on IRC so we can look out for you rather than hiding in the corner. Optionally you could ask at the bar if they know where the geeky computer weirdos are and they'll point you in the right direction (seriously!). Another possibility is look for heaps of electronics on a table that may possibly look like movie props that would used for detonating explosives. Feel free to bring electronics/laptops/gadgets to the meet, you will by no means be alone. Ben Bewick aka Viperfang NB: This mail is automated, please refer to the usual sources for more information. ALUG Contact Details: Website : http://www.alug.org.uk/ IRC : #alug on irc.alug.org.uk List : http://lists.alug.org.uk/mailman/listinfo Twitter : http://twitter.com/anglianlug Identica: TBA Facebook: http://www.facebook.com/group.php?gid=2381613902 ----- Send discussion replies to main(a)lists.alug.org.uk (Reply-To set) Unsub, change settings via https://lists.alug.org.uk/mailman/listinfo/announce

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