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Network issues with github
by Alex Beamish 30 Nov '20

30 Nov '20

Hi All, This is probably a blindingly obvious question, but I'm a little stumped. I've done a little work for local business, setting up a Linux server (Ubuntu), developing some code and pushing it to github. It's all worked wonderfully until a few weeks ago, when he had someone in to do something to the network. Since then, Things Are Broken in ways that I don't understand. When I try to do anything with github, I see the response Received disconnect from 140.82.113.3 port 22:2: Connection blocked because server only allows public key authentication. Please contact your network administrator. Because I was worried I'd borked my account, this afternoon I tried again, creating a brand-new account and ssh-ing in .. and still got the same result. My github account works fine from my own machine, and also from my web provider (pair.com) so I'm guessing there's something going on within my client's network. Suggestions gratefully received. Alex -- Alex Beamish Software Developer / https://ca.linkedin.com/in/alex-beamish-5111ba3 Speaker Wrangler / Toronto Perlmongers / http://to.pm.org/ Chair, Sponsorship Committee, TPF / https://www.perlfoundation.org/ Baritone, Operations Manager / Toronto Northern Lights, 2013 Champions / www.northernlightschorus.com

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Fedora 33 uses RAM for swap?
by Giles Orr 25 Nov '20

25 Nov '20

A few days after upgrading the last of my machines from Fedora 32 to 33, I noticed my main machine has acquired a new disk: NAME SIZE FSTYPE LABEL MOUNTPOINT zram0 4G [SWAP] I didn't set that up, and I don't think it was there on F32. So the OS has, without asking, co-opted 1/4 of my 16G of RAM to use as swap space. This system has an SSD, so when I initially set it up (Fedora 27), I made a conscious decision to go without swap space. I rarely push the limits of 16G. But now I'm in the situation that I have only 12G of RAM, so the system will become memory-starved earlier ... and what will it do? It will go to swap. Which is RAM anyway. How does this help? To me this seems like adding complexity without adding utility. Can someone please explain A) if I'm correct about this behaviour in the first place, and B) why it's useful? Thanks. -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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security threats of Open Source
by D. Hugh Redelmeier 25 Nov '20

25 Nov '20

<https://www.zdnet.com/article/microsoft-spots-malicious-npm-package-stealin…> This article list six cases of malware contributed to npm (the repo for sharing node.js and JavaScript source). How many undetected cases exist? I've alway pretended that Linux distros vet their code. I'm not sure how true that is. Probably the greatest protection is the time delay between contribution and distribution. I wonder what can be done about this problem. I've said so at our meetings a few times too. Of course the problem is worse with closed source: it is impossible to audit the source. But closed source might have fewer contributors and more supervision. Of course much closed soure is built on top of open source and thuse all its weakness

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Re: [GTALUG] Reverse DNS different that DNS server (reverse is a local address)
by Joseph Rocklin 23 Nov '20

23 Nov '20

Thanks for the feedback. I have a lot more learning ahead. I will try to concisely post questions, only when needed, in future. I appreciate your collective help. Sincerely, Joseph 23 Nov 2020, 10:14 am by talk(a)gtalug.org: > On Mon, 23 Nov 2020 09:20:57 -0500 (EST) > "D. Hugh Redelmeier via talk" <talk(a)gtalug.org> wrote: > >> I have no time for a careful answer. But it is important that you >> understand these points: >> > I can also spend a few minutes to add to the points below, if > that helps anyone... > >> - DNS is a distributed tree, with nodes that are authoritative for >> particular domains. >> > Yes, and not at all - names = not so much, possibly, a little like a > one or two branch tree - Numbers = always four or six "branches" > > DNS is mostly a fixed single easy thing. (although you do get weird > 'trees' like de.li.cio.us (or whatever that was) > > For names it could resemble a tree with one sometimes two or thee > branches, hardly ever more than that... (in theory it could have > millions of branches - but IRL (in real life) two or three... > > An example - would be example.com > .com says which NS server(s) is/are authorative for example > > That NS server(s) may further say where is www.example.com > > but not often do you find www.www.www.www.example.com > (although you could, in theory, have a "tree", I guess...) > > for numbers though, the delegation is only 4 "branches" deep for ipv4 > and 6 "branches" deep for ipv6 - unless you count the main .in-addr.arpa > as another two? > > So, DNS may be a bit like a very small bonsai? hehehehe > > >> - there is caching (recursive servers) if you trust them (almost >> always one does). Unless you are using DNSSec, the caching server >> can lie, sometimes usefully. >> >> - the forward domain is technically unrelated to the reverse domain. >> > yes, reverse and forward lookup is not related, but when they match, as > in for use as an email server, this is another layer in the onion of > trust. > > and, technically - it is ALL forward lookups (even a reverse lookup :) > the 'reverse' is actually you/inquirer 'reversing' the number and > adding .in-addr.arpa ) > >> The forward domain lookup uses a conventional domain name as the >> key. >> > > You can have 192.168.1.100.com - so the only 'convention' is that > forward and reverse both has 'sub domains' > > it is all really 'forward' lookups :) > > forward works from the back > 123 -> com for 123.com > > reverse works by "reversing the number" and adding .in-addr.arpa > > 192.168.1.1 -> 192 for 168 > so: 1.2.168.192.in-addr.arpa > > for example: dig NS 136.100.in-addr.arpa tells you how 136.100 is > delegated, etc etc. > >> The reverse lookup uses the IP address (in a funny format) as the >> key. >> > not so funny, just the normal ip number format > > but the reverse is from the start of the number and not the end > >> - Reverse example: to lookup the reverse for IPv4 address 1.2.3.4, >> your system actually queries 4.3.2.1.in-addr.arpa. I think you can >> see how that is constructed. >> > yes, this is all it is :) > >> - the reverse domain is a mystery to most people (because it mostly >> doesn't matter to most users). If you run a mail server, it does >> matter. >> - whoever provided you with your IP address controls the reverse >> domain for that IP address. Generally, if you pay for a static IP >> address, they will let you specify what you want them to put in the >> reverse domain for that IP address. Most ordinary consumers don't >> have static addresses and are not given a say in what the reverse >> says. >> > if whomever provided you with the number did not hijack it from > somewhere and it is in fact properly delegated, then they could, in > their own auth NS, add whatever 'name' you like to the IP number :) > >> - if your provider provides you with a CIDR of network addresses, >> static, they may delegate the reverse domain for that CIDR to a DNS >> of your choosing. This is not the normal home case. >> > > --- > Post to this mailing list talk(a)gtalug.org > Unsubscribe from this mailing list https://gtalug.org/mailman/listinfo/talk >

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Reverse DNS different that DNS server (reverse is a local address)
by Joseph Rocklin 23 Nov '20

23 Nov '20

Hi all, I just tried a reverse dns lookup on whoismydns.com for my wife's computer on a family-member's network. Result: DNS Server: 67.231.208.167 Reverse DNS: pub-cdns3-wlfdle-eth1.rpub.net.rogers.com IP Owner: Rogers Does this seem correct? I have my dns settings set on my machine and I get my expected DNS results on my machine on this family member's network. Is there any reason to be concerned here? I had noticed a while back, before upgrades on this family member's network, that utopia.net was being used as the DNS server. It was on more than one machine that used that network. Now I'm wondering if somehow this network was routing, in a still-problematic way, but just via a local address? I may have confused some concepts as I am just getting my feet wet with this topic of DNS servers. If anyone has suggestions to confirm if the network is properly setup, please let me know. Thank you, Joseph Rocklin,

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saving files in multiple locations
by o1bigtenor 19 Nov '20

19 Nov '20

Greetings I'm wanting to save a file (from a text editor) in multiple locations simply and easily. I've looked at 'parallel' and ran into the idea of symlink chains but so far parallel seems more for multiple in and out and symlink chains besides a reference I can't find more information. I think the rsync and cron would likely create a plethora of files which would then need cleaning so as not to waste too much space. So - - - - I dunno where to look next - - - please? TIA

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how to save multiple copies of a file
by o1bigtenor 19 Nov '20

19 Nov '20

Greetings I'm wanting to save a file (from a text editor) in multiple locations simply and easily. I've looked at 'parallel' and ran into the idea of symlink chains but so far parallel seems more for multiple in and out and symlink chains besides a reference I can't find more information. I think the rsync and cron would likely create a plethora of files which would then need cleaning so as not to waste too much space. So - - - - I dunno where to look next - - - please? TIA

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First new home computer for decades - Raspberry Pi 400
by Stewart Russell 13 Nov '20

13 Nov '20

... and it runs Linux. https://www.raspberrypi.org/products/raspberry-pi-400/?resellerType=home

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Freedom and Graphene
by Evan Leibovitch 13 Nov '20

13 Nov '20

Hi all, It's 2020 and a long time since Shaw bought Wind Mobile and renamed it to Freedom. So I wonder if it's worth another look. Prices are as always aggressive but questions remain about speed and coverage. The reason I want a new phone plan is because I'm experimenting with a new phone on which I've just installed GrapheneOS; more than just another Android ROM, it's touted as being one of the most privacy-focused phones one can have. Google-free, of course, beyond what's in AOSP, and two different app stores to replace Google Play. Does anyone here have experience with either Freedom Mobile or GrapheneOS? Any answers are much appreciated. If there's interest I'll be happy to talk about my experiences with GrapheneOS at a future GTALUG meeting. Evan Leibovitch, Toronto Canada @evanleibovitch / @el56

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Christopher Browne
by Stewart C. Russell 12 Nov '20

12 Nov '20

It is with great sadness that I have to inform you that Chris Browne passed away on Monday. Chris held many roles on the GTALUG board over the years, and his contributions to the group - both social and technical - are beyond measure. Visitation is at Capital Funeral Home & Cemetery, 3700 Prince of Wales Drive, Ottawa on Wednesday, November 11 from 5:00 – 8:00pm. A Funeral Service will be held at The Metropolitan Bible Church, 2176 Prince of Wales Drive on Thursday, November 12 at 11:00am On behalf of GTALUG, condolences go to Chris's family. Obituary: https://www.arbormemorial.ca/capital/obituaries/christopher-bruce-browne/57… Thanks to Andrew Heagle for passing the news along earlier this afternoon. Stewart

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