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#mastodon #fediverse #socialmedia

00:00 Intro
00:39 Sponsor: Extend the life of your Python applications
01:30 The Fediverse: a network of social networks
04:57 ActivityPub: all your social networks can talk to each other
06:44 How Mastodon works
08:33 How PeerTube works
10:19 How PixelFed works
11:39 Parting thoughts
13:02 Sponsor: buy a device that runs Linux perfectly
14:11 Support the channel

Join Mastodon: https://joinmastodon.org/servers
Join Peertube: https://joinpeertube.org/
Join PixelFed: https://pixelfed.org/servers

PixelFed App for iOS: https://testflight.apple.com/join/5HpHJD5l
PixelFed App for Android: https://f-droid.org/en/packages/org.pixeldroid.app/

List of Fediverse services: https://fediverse.party/en/miscellaneous/

Fediverse is a contraction of Federated Universe. It's basically a very large network of servers that form, well, a social network. But contrary to the ones you might be used to, like Facebook, Twitter, Instagram, and others, the Fediverse is composed of different services.

The more well known are Mastodon, a Twitter-like microblogging service, PeerTube, a youtube-like platform, or PixelFed, an Instagram-like social network, but there are a TON of others.

Each service is also decentralized, which means there is not one big server farm where everything is hosted: each service is split into instances, basically independent servers, with different goals.

ActivityPub is an open standard, that lets all services on the Fediverse talk to each other. How does that work? Well, in practice, it means you can use your Mastodon app to follow a Peertube channel, or someone that posts pictures on PixelFed, or see new articles from a Wordpress website.

And this goes a bit further: for example, if I comment on Mastodon on a post from Peertube, that comment will also appear on Peertube underneath the video.

Let's start with Mastodon. Mastodon is basically Twitter, but open source and decentralized. It lets you post messages with up to 500 characters, it supports images, videos, polls, content warnings, animated avatar pictures, emojis, links, mentions, hashtags, anything you're used to on Twitter. Mastodon has 1.5 million active users, which might seem small compared to Twitter, but it's more than enough to have interesting conversations with a lot of cool people.

To join Mastodon, all you need to do is pick a server, also called an instance. You can pick any server you like, and it will let you interact with everyone else on any other server.

And then, you can use Mastodon on the web, by typing the address of your instance in your browser, for example, for me, it's mastodon.social, or you can use a mobile app.

Now let's talk about PeerTube. It's a Youtube alternative, although it's much, much smaller. Peertube is also decentralized, being split into different servers, that are federated together, so you can follow people from different instances and still have a complete subscription feed. It also supports ActivityPub, which means you could subscribe to my peerTube channel from a mastodon account, and have a post in your timeline every time I publish a video.

And as a creator, it also lets you sync your youtube channel to it, so you can auto-publish all your videos to Peertube in a few clicks, which is also a great help.

To watch peertube, just type the address of your instance in your browser's URL, for me it's tilvids.com.

Another cool service on the Fediverse is PixelFed. It's basically Instagram, without all the crap they tacked on lately, like reels, or lives. It's just pictures and videos. It's free software, it also uses the ActivityPub standard, so you can follow PixelFed users on Mastodon, for example, and it's ad-free.

It also lets you add filters, just like Instagram, or crop, resize, adding alt text, and you can use hashtags, locations, or create collections, basically photo albums.

Here's another #post-mortem for you.

Tl;dr: Be sure your diagnostic tools show everything and do not hide vital information even though running in verbose or verbose-verbose mode.

First of all: My home #network is not as simple as it could be and certainly not as simple as it would be with most private users around the globe.
That brings with it its very own bunch of challenges, none of which is of any particular concern here. Suffice it to say, a regular consumer-grade internet access device (colloquially "WiFi router") would not do it. I have heavier requirements.

That in turn means my #ISP did not supply me with a real router – in fact I decline any ISP-supplied device whenever possible. Instead I bought my own device which does fulfill my requirements, in this case a semi-professional router with #PPPoE #pass-through capabilities, essentially a #DSL‌-modem.

The latter is the important part, because that is where my weekend worries began.

The modem did work for years on end with no reason for me to ever regret my decision to buy it in the first place.
Until last friday morning when it rebooted from the latest firmware upgrade.

At that very moment my internet connection dropped with a very dreaded error message from the #PPP daemon: "Timeout waiting for PADO packets."
That's tech-talk for "the ISP does no longer reply to my connection requests."

The message was already known to me and experience had me on the side of stupid coincidence which I have seen more often than I could count. So, quickly I was on the phone with the ISP requesting a port reset hoping for instant recovery.
Which didn't happen.

I'll skip the boring part of booting, downgrading, recabling and testing (even with a new OS install) for hours while other people expected me to work, but it went on until monday morning. Needless to say, I had a lot of time to think during the weekend.

I will just mention that most of the time I got beyond that PADO step, yet #pppd failed to get any replies for its #LCP configuration requests (that way I can add some more hashtags to the post, yay!).

On monday morning I finally figured I should do a real trace of the conversation appearing on the wire, for as far as #tcpdump told me not only was I sending requests, I even got answers from the ISP. Only, they were ignored by my endpoint software.
tcpdump's console output did not reveal why this should happen, a different network card, updated endpoint software - nothing actually helped. Requests were sent, replies came in and were promptly ignored.

Until I was fed up enough and decided to have a deep look into that very conversation on the wire, using #wireshark. Wireshark is a very powerful tool and its most notable feature is it doesn't hide any information by default.
And it was this now unhidden information which finally pointed me in the right direction: The oh-so-dutifully ignored replies from my ISP carried with them a #VLAN tag.

Short excursion: I am using a #VDSL landline on which the provider offers "triple-play", that is, Internet, Telephone and TV all over the same cable. For that to work technically, the ISP requires its customers to tag their "regular" outgoing internet traffic with a certain VLAN id before sending it out to the ISP. Likewise, the ISP tags all incoming internet traffic with same id.

Usually, the modem should do the tag/untag of the traffic before handing it over to the LAN, in my case to my PPP endpoint.
And it was this very tag/untag which actually stopped working.

From this point on the solution was pretty simple: If the tagging inside the modem is unreliable, the feature can be disabled (in fact, it can be configured to suit the ISP's requirements). So I did that. Now that caused the situation to deteriorate in the first step, because now nothing was coming back at all anymore. Where at least I got ignored replies from the ISP before now I got nothing.

However, #linux is capable of a lot of things, one of which is making network cards do "the right thing". In this case I reconfigured the system's network to add the required VLAN tag to everything related to the much needed PPP connection. A side effect is that the kernel now also removes the tag from any incoming frame.
At this point my PPP endpoint finally got the replies again and within seconds the connection was back up as it was designed in the first place.

Needless to say I think it's a bug in the modem's firmware, yet since downgrading did not improve the situation, it seems the bug was introduced much earlier but never manifested itself.
Also, to reference the "tl;dr" from above: Had I done the wireshark trick right from the start I probably would have stumbled over the wrong VLAN tag much earlier, saving me a lot of testing hours as well as a lot of worries on how to get the system back to its intended state.
The lesson I learned is that even though diagnostic tools can be made to be very verbose, sometimes they still skip some information vital to the issue in question and thus can not necessarily be fully trusted. It is not only important to have those tools at hand, it is quite as important to know their limitations and how to handle or overcome them.

@HogwartsGraduated ♂️🏳️‍🌈♈💉 es empfiehlt sich die E-Mails über einen ordentlich konfigurierten E-Mailserver oder über einen E-Mailanbieter zu verschicken falls du keinen eigenen Mailserver betreibst.

Mit msmtp kannst du #Linux so konfigurieren, dass es ein anderes SMTP Postfach nutzen kann.

Such mal bei einer Suchmaschine, da gibt es ein paar gute Anleitungen.
Bspw. hier:
https://wiki.debian.org/msmtp
oder hier:
https://wiki.archlinux.org/title/msmtp

Such eine für Dein Linux und richte es ein. Es gibt zwei Konfigurationen die man machen muss, eine /etc/ und eine im Homeverzeichnis des Users unter dem der Webserver läuft.

Wichtiger Tipp für Anfänger, mach regelmäßig ein Backup der Datenbank und des Webroots, denn Deine Domain wird unbrauchbar wenn du erstmal im #Fediverse aktiv bist kannst du nicht einfach noch mal neu installieren, du musst also immer alle Probleme lösen, dabei ist manchmal ein Backup hilfreich.

@Roland Häder@diritschka@Bionk

The pdf annotation software I started using early on my career was Mendeley, back when it was an open-source independent project. Then it was bought my Elsevier, its code became private, and a sort of social network was built around its user data-base. No thank you, I won't give my data to such an evil publishing machine.
I then switched to Polar. It was independent, light-weight, open-source... Really nice! But the creators of the project started complaining they were not receiving any support from users (before they even released their first stable version), they started using google code, closed the source-code, and then again everything went to downhill...
I thought I would never find a decent, open-source, independently developed academic library. I annotate my pdfs, write comments on them, etc. And I need to have the ordered by topic, authors, and all the relevant metadata.
And then I realized the answer was in front of me this whole time! Okular! The pdf reader that comes with KDE (linux) implemented a lot of options that allow to highlight, underline, annotate, etc your pdfs. The interface is great, the software is very lightweight, works flawlessly, and I can be sure it will remain open-source.
The only thing I am missing is a dedicated library to manage my pdfs, but honestly, I can do that myself by keeping an ordered and systematic system to store my library on my hard-drives, with some backup in the cloud.

#linux #foss #pdfs #Mendeley #Polar #Okular #Kde #opensource #academia #science