Thunar, the Xfce4 file manager, has a bug that it underflows the time remaining for a file copy since ten years now (bugzilla, gitlab). Happy birthday!

Update from 01.06.2023:

Good news, Debian Bookworm will also be released with this long term friend still present. Phew!

Update from 28.04.2022: Do not use the packages below any more. There is Netatalk 3.1.13 out with fixes for multiple remote code execution (RCE) bugs. Use packages from recent Debian again, they have been updated.

Netatalk 3.1.12 has been released which fixes an 18 year old RCE bug. The Medium write up on CVE-2018-1160 by Jacob Baines is quite an entertaining read.

The full release notes for 3.1.12 are unfortunately not even half as interesting.

Be sure to read the original blog post if you are new to Netatalk3 on Debian Jessie or Stretch! You'll get nowhere if you install the .debs below and don't know about the upgrade path from 2.2.x which is still in the Debian archive. So RTFA.

For Debian Buster (Debian 10) we'll have Samba 4.9 which has learnt (from Samba 4.8.0 onwards) how to emulate a SMB time machine share. I'll make a write up how to install this once Buster stabilizes. This luckily means there will be no need to continue supporting Netatalk in normal production environments. So I guess bug #690227 won't see a proper fix anymore. Waiting out problems helps at times, too :/.

Update instructions and downloads:

So, your machine now needs minutes to boot before you can ssh in where it used to be seconds before the Debian Buster update?

Problem

Linux 3.17 (2014-10-05) learnt a new syscall getrandom() that, well, gets bytes from the entropy pool. Glibc learnt about this with 2.25 (2017-02-05) and two tries and four years after the kernel, OpenSSL used that functionality from release 1.1.1 (2018-09-11). OpenSSH implemented this natively for the 7.8 release (2018-08-24) as well.

Now the getrandom() syscall will block¹ if the kernel can't provide enough entropy. And that's frequenty the case during boot. Esp. with VMs that have no input devices or IO jitter to source the pseudo random number generator from.

First seen in the wild January 2017

I vividly remember not seeing my Alpine Linux VMs back on the net after the Alpine 3.5 upgrade. That was basically the same issue.

Systemd. Yeah.

Systemd makes this behaviour worse, see issues #4271, #4513 and #10621.
Basically as of now the entropy file saved as /var/lib/systemd/random-seed will not - drumroll - add entropy to the random pool when played back during boot. Actually it will. It will just not be accounted for. So Linux doesn't know. And continues blocking getrandom(). This is obviously different from SysVinit times² when /var/lib/urandom/random-seed (that you still have lying around on updated systems) made sure the system carried enough entropy over reboot to continue working right after enough of the system was booted.

#4167 is a re-opened discussion about systemd eating randomness early at boot (hashmaps in PID 0...). Some Debian folks participate in the recent discussion and it is worth reading if you want to learn about the mess that booting a Linux system has become.

While we're talking systemd ... #10676 also means systems will use RDRAND in the future despite Ted Ts'o's warning on RDRAND [Archive.org mirror and mirrored locally as 130905_Ted_Tso_on_RDRAND.pdf, 205kB as Google+ will be discontinued in April 2019].
Update: RDRAND doesn't return random data on pre-Ryzen AMD CPUs (AMD CPU family <23) as per systemd bug #11810. It will always be 0xFFFFFFFFFFFFFFFF (2⁶⁴-1). This is a known issue since 2014, see kernel bug #85991.

Debian

Debian is seeing the same issue working up towards the Buster release, e.g. Bug #912087.

The typical issue is:

with delays up to tens of minutes on systems with very little external random sources.

This is what it should look like:

Check dmesg | grep -E "(rng|random)" to see how your systems are doing.

If this is not fully solved before the Buster release, I hope some of the below can end up in the release notes³.

Solutions

You need to get entropy into the random pool earlier at boot. There are many ways to achieve this and - currently - all require action by the system administrator.

Kernel boot parameter

From kernel 4.19 (Debian Buster currently runs 4.18 [Update: but will be getting 4.19 before release according to Ben via Mika]) you can set RANDOM_TRUST_CPU at compile time or random.trust_cpu=on on the kernel command line. This will make recent Intel / AMD systems trust RDRAND and fill the entropy pool with it. See the warning from Ted Ts'o linked above.

Update: Since Linux kernel build 4.19.20-1 CONFIG_RANDOM_TRUST_CPU has been enabled by default in Debian.

Using a TPM

The Trusted Platform Module has an embedded random number generator that can be used. Of course you need to have one on your board for this to be useful. It's a hardware device.

Load the tpm-rng module (ideally from initrd) or compile it into the kernel (config HW_RANDOM_TPM). Now, the kernel does not "trust" the TPM RNG by default, so you need to add

rng_core.default_quality=1000

to the kernel command line. 1000 means "trust", 0 means "don't use". So you can chose any value in between that works for you depending on how much you consider your TPM to be unbugged.

VirtIO (KVM, QEMU, ...)

For Virtual Machines (VMs) you can forward entropy from the host (that should be running longer than the VMs and have enough entropy) via virtio_rng.

So on the host, you do:

kvm ... -object rng-random,filename=/dev/urandom,id=rng0 -device virtio-rng-pci,rng=rng0,bus=pci.0,addr=0x7

and within the VM newer kernels should automatically load virtio_rng and use that.

You can confirm with dmesg as per above.

Or check:

Patching systemd

The Fedora bugtracker has a bash / python script that replaces the systemd rnd seeding with a (better) working one. The script can also serve as a good starting point if you need to script your own solution, e.g. for reading from an entropy provider available within your (secure) network.

Chaoskey

The wonderful Keith Packard and Bdale Garbee have developed a USB dongle, ChaosKey, that supplies entropy to the kernel. Hard- and software are open source.

Jitterentropy_RNG

Kernel 4.2 introduced jitterentropy_rng which will use the jitter in CPU timings to generate randomness.

modprobe jitterentropy_rng

This apparently needs a userspace daemon though (read: design mistake) so

apt install jitterentropy-rngd (available from Buster/testing).

The current version 1.0.8-3 installs nicely on Stretch. dpkg -i is your friend.

But - drumroll - that daemon doesn't seem to use the kernel module at all.

That's where I stopped looking at that solution. At least for now. There are extensive docs if you want to dig into this yourself.

Update: The Linux kernel 5.3 will have an updated jitterentropy_rng as per Commit 4d2fa8b44. This is based on the upstream version 2.1.2 and should be worth another look.

Haveged

apt install haveged

Haveged is a user-space daemon that gathers entropy though the timing jitter any CPU has. It will only run "late" in boot but may still get your openssh back online within seconds and not minutes.

It is also - to the best of my knowledge - not verified at all regarding the quality of randomness it generates. The haveged design and history page provides and interesting read and I wouldn't recommend haveged if you have alternatives. If you have none, haveged is a wonderful solution though as it works reliably. And unverified entropy is better than no entropy. Just forget this is 2018 2019 .

early-rng-init-tools

Thorsten Glaser has posted newly developed early-rng-init-tools in a debian-devel thread. He provides packages at http://fish.mirbsd.org/~tg/Debs/dists/sid/wtf/Pkgs/early-rng-init-tools/ .

First he deserves kudos for naming a tool for what it does. This makes it much more easily discoverable than the trend to name things after girlfriends, pets or anime characters. The implementation hooks into the early boot via initrd integration and carries over a seed generated during the previous shutdown. This and some other implementation details are not ideal and there has been quite extensive scrutiny but none that discovered serious issues. Early-rng-init-tools look like a good option for non-RDRAND (~CONFIG_RANDOM_TRUST_CPU) capable platforms.

Linus to the rescue

Luckily end of September Linus Torvalds was fed up with the entropy starvation issue and the non-conclusive discussions about (mostly) who's at fault and ... started coding.

With the kernel 5.4 release on 25.11.2019 his patch has made it into mainline. He created a try_to_generate_entropy function that uses CPU jitter to generate seed entropy for the PRNG early in boot.

In the merge commit Linus explains:

This is admittedly partly "for discussion". We need to have a way forward for the boot time deadlocks where user space ends up waiting for more entropy, but no entropy is forthcoming because the system is entirely idle just waiting for something to happen.

While this was triggered by what is arguably a user space bug with GDM/gnome-session asking for secure randomness during early boot, when they didn't even need any such truly secure thing, the issue ends up being that our "getrandom()" interface is prone to that kind of confusion, because people don't think very hard about whether they want to block for sufficient amounts of entropy.

The approach here-in is to decide to not just passively wait for entropy to happen, but to start actively collecting it if it is missing. This is not necessarily always possible, but if the architecture has a CPU cycle counter, there is a fair amount of noise in the exact timings of reasonably complex loads.

We may end up tweaking the load and the entropy estimates, but this should be at least a reasonable starting point.

So once this kernel is available in your distribution, you should be safe from entropy starvation at boot on any platform that has hardware timers (I haven't encountered one that does not in the last decade).

Ted Ts'o reviewed the approach and was fine and Ahmed Dawish did some testing of the quality of randomness generated and that seems fine, too.

Updates

14.01.2019

Stefan Fritsch, the Apache2 maintainer in Debian, OpenBSD developer and a former Debian security team member stumbled over the systemd issue preventing Apache libssl to initialize at boot in a Debian bug #916690 - apache2: getrandom call blocks on first startup, systemd kills with timeout.

The bug has been retitled "document getrandom changes causing entropy starvation" hinting at not fixing the underlying issue but documenting it in the Debian Buster release notes.

Unhappy with this "minimal compromise" Stefan wrote a comprehensive summary of the current situation to the Debian-devel mailing list. The discussion spans over December 2018 and January 2019 and mostly iterated what had been written above already. The discussion has - so far - not reached any consensus. There is still the "systemd stance" (not our problem, fix the daemons) and the "ssh/apache stance" (fix systemd, credit entropy).

The "document in release notes" minimal compromise was brought up again and Stefan warned of the problems this would create for Buster users:

> I'd prefer having this documented in the release notes:
> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=916690
> with possible solutions like installing haveged, configuring virtio-rng,
> etc. depending on the situation.

That would be an extremely user-unfriendly "solution" and would lead to 
countless hours of debugging and useless bug reports.

This is exactly why I wrote this blog entry and keep it updated. We need to either fix this or tell everybody we can reach before upgrading to Buster. Otherwise this will lead to huge amounts of systems dead on the network after what looked like a successful upgrade.

Some interesting tidbits were mentioned within the thread:

Raphael Hertzog fixed the issue for Kali Linux by installing haveged by default. Michael Prokop did the same for the grml distribution within its December 2018 release.

Ben Hutchings pointed to an interesting thread on the debian-release mailing list he kicked off in May 2018. Multiple people summarized the options and the fact that there is no "general solution that is both correct and easy" at the time.

Sam Hartman identified Debian Buster VMs running under VMware as an issue, because that supervisor does not provide virtio-rng. So Debian VMs wouldn't boot into ssh availability within a reasonable time. This is an issue for real world use cases albeit running a proprietary product as the supervisor.

16.01.2019

Daniel Kahn Gillmor wrote in to explain a risk for VMs starting right after the boot of the host OS:

If that pool is used by the guest to generate long-term secrets because it appears to be well-initialized, that could be a serious problem.
(e.g. "Mining your P's and Q's" by Heninger et al -- https://factorable.net/weakkeys12.extended.pdf)
I've just opened https://bugs.launchpad.net/qemu/+bug/1811758 to report a way to improve that situation in qemu by default.

So ... make sure that your host OS has access to a hardware random number generator or at least carries over its random seed properly across reboots. You could also delay VM starts until the crng on the host Linux is fully initialized (random: crng init done).
Otherwise your VMs may get insufficiently generated pseudo-random numbers and won't even know.

12.03.2019

Stefan Fritsch revived the thread on debian-devel again and got a few more interesting tidbits out of the developer community:

Ben Hutchings has enabled CONFIG_RANDOM_TRUST_CPU for Debian kernels from 4.19.20-1 so the problem is somewhat contained for recent CPU AMD64 systems (RDRAND capable) in Buster.

Thorsten Glaser developed early-rng-init-tools which combine a few options to try and get entropy carried across boot and generated early during boot. He received some scrutiny as can be expected but none that would discourage me from using it. He explains that this is for early boot and thus has initrd integration. It complements safer randomness sources or haveged.

16.04.2019

The Debian installer for Buster is running into the same problem now as indicated in the release notes for RC1. Bug #923675 has details. Essentially choose-mirror waits serveral minutes for entropy when used with https mirrors.

08.05.2019

The RDRAND use introduced in systemd to bypass the kernel random number generator during boot falls for a AMD pre-Ryzen bug as RDRAND on these systems doesn't return random data after a suspend / resume cycle. Added an update note to the systemd section above.

03.06.2019

Bastian Blank reports the issue is affecting Debian cloud images now as well as cloud-init generates ssh keys during boot.

10.07.2019

Added the update of jitterentropy_rng to a version based on upstream v2.1.2 into the Jitterentropy section above.

16.09.2019

The Linux Kernel Mailing List (LKML) is re-iterating the entropy starvation issue and the un-willingness of systemd to fix its usage of randomness in early boot. Ahmed S. Darwish has reported the issue leading to ext4 reproducibly blocking boot with Kernel 5.3-r8. There are a few patches floated and the whole discussion it worth reading albeit non-conclusive as of now.

Ted Ts'o says "I really very strongly believe that the idea of making getrandom(2) non-blocking and to blindly assume that we can load up the buffer with 'best efforts' randomness to be a terrible, terrible idea that is going to cause major security problems that we will potentially regret very badly. Linus Torvalds believes I am an incompetent systems designer." in this email.

In case you needed a teaser to really start reading the thread! Linus Torvalds also mentions the issue (and a primer on what "never break userspace" means) in the Linux kernel 5.3 release notes.

18.09.2019

... and Martin Steigerwald kindly noticed that I update this blog post with the relevant discussions I come across as this entropy starvation mess continues to haunt us.

25.11.2019

Added the "Linus to the rescue" section after the Linux kernel 5.4 has been released.

02.04.2020

I ran into the same issue on a Gentoo system today. Luckily OpenRC handeled this gracefully but it delayed booting: syslog-ng actually hangs the boot for some time ... waiting for entropy. Argh. The Gentoo forums thread on the topic clearly listed the options:

1. Make syslog-ng depend on haveged by adding rc_syslog_ng_need="haveged" to /etc/rc.conf (and obviously having haveged installed)
2. Re-compiling the kernel with CONFIG_RANDOM_TRUST_CPU=y where that is an option

Firefox on Linux can develop the habit to (rather randomly) ask again and again to be made the default browser. E.g. when started from Thunderbird by clicking a link it asks but when starting from a shell all is fine.

The reason to this is often two (or more) .desktop entries competing with each other.

So, walkthrough: (GOTO 10 in case you are sure to have all the basics right)

should both show firefox for you. If not

the entry to fix the preference on /usr/bin/firefox.

Check (where available)

that the "Internet Browser" is "Firefox".

Check (where available)

that anything containing "html" points to Firefox (or is left at a non-user set default).

Check (where available)

that you get firefox.desktop. If not run

If you are running Gnome, check

and the same for https.

LABEL 10:

Run

and remove all entries that contain something like userapp-Firefox-<random>.desktop.

Run

and delete these files or move them away.

Done.

Once you have it working again consider disabling the option for Firefox to check whether it is the default browser. Because it will otherwise create those pesky userapp-Firefox-<random>.desktop files again.

Configuring Linux is easy, innit?

I use a headset to make phone calls and when they are mono the great awesomeness of the Linux audio stack seems to change volume only on the active channel (e.g. the right channel). So when I listen to some music (stereo) afterwards the channels are not balanced anymore and one side is louder than the other. And this persists thanks to saving the preferences across reboots. Duh.

As usually checking Pulseaudio (pavucontrol) is useless, it shows balanced channels.

But checking Alsa (alsamixer) revealed the issue and alsamixer can fix this, too:

Step 1: run alsamixer in a terminal and select your headset after pressing [F6]:

Step 2: Select the headset audio output with [<-] and [->] cursor keys:

Step 3: Press [b] to balance the left and right channels:

Step 4: Press [Esc] to exit alsamixer which will keep the changed settings (... great choice of key, [q] raises the left channel's loundness ...).

Step 5: Save this setting by running sudo alsactl store which should update /var/lib/alsa/asound.state with the fixed settings so they persist across reboots.

Step 6: Enjoy music again .

If you need to script this, amixer is the tool to use, e.g. amixer -c 1 set "Headset" 36.
1 is the card number which you see in alsamixer, "Headset" is the channel name, also from alsamixer (which can contain blanks, hence the quotes around the name) and 36 is the desired loundness level for both channels. See the screenshots above where to find the data or run aplay -l to see the cards on your PC and amixer -c 1 (with your card id) to see the channels that (virtual, USB) sound card has.

Debian is moving the git hosting from alioth.debian.org, an instance of Fusionforge, to salsa.debian.org which is a Gitlab instance.

There is some background reading available on https://wiki.debian.org/Salsa/. This also has pointers to an import script to ease migration for people that move repositories. It's definitely worth hanging out in #alioth on oftc, too, to learn more about salsa / gitlab in case you have a persistent irc connection.

As of now() salsa has 15,320 projects, 2,655 users in 298 groups.
Alioth has 29,590 git repositories (which is roughly equivalent to a project in Gitlab), 30,498 users in 1,154 projects (which is roughly equivalent a group in Gitlab).

So we currently have 50% of the git repositories migrated. One month after leaving beta. This is very impressive.
As Alioth has naturally accumulated some cruft, Alexander Wirt (formorer) estimates that 80% of the repositories in use have already been migrated.

So it's time to update your local .git/config URLs!

Mehdi Dogguy has written nice scripts to ease handling salsa / gitlab via the (extensive and very well documented) API. Among them is list_projects that gets you nice overview of the projects in a specific group. This is especially true for the "Debian" group that contains the former collab-maint repositories, so source code that can and shall be maintained by Debian Developers collectively.

Finding migrated repositories

Salsa can search quite quickly via the Web UI: https://salsa.debian.org/search?utf8=✓&search=htop

but finding the URL to clone the repository from is more clicks and ~4MB of data each time (yeah, the modern web), so

is a bit nicer.

Please notice the git url format is a bit odd, it's either
git@salsa.debian.org:debian/htop.git or
ssh://git@salsa.debian.org/debian/htop.git.

Notice the ":" -> "/" after the hostname. Bit me once.

Finding repositories to update

At this time I found it useful to check which of the repositories I have cloned had not yet been updated in the local .git/config:

Thanks to Jörg Jaspert (Ganneff) the Debconf repositories have all been moved to Salsa now.
Hint: Bug him for his scripts if you need to do complex moves.

Updating the URLs has been an hours work on my side and there is little you can do to speed that up if - as in the Debconf case - teams have used the opportunity to clean up and things are not as easy as using sed -i.

But there is no reason to do this more than once, so for the laptops...

Speeding up migration on multiple devices

will rsync the .git/config files that you changed to other systems where you keep partial copies.

On these a simple git pull to get up to remote HEAD or using the git_pull_all one-liner from https://daniel-lange.com/archives/99-Managing-a-project-consisting-of-multiple-git-repositories.html will suffice.

Git short URL

Stefano Rivera (tumbleweed) shared this clever trick:

This way you can git clone salsa:debian/htop.

One of the perks you get as a Debian Developer is a @debian.org email address. And because Debian is old and the Internet used to be a friendly place this email address is plastered all over the Internet. So you get email spam, a lot of spam.

I'm using a combination of server and client site filtering to keep spam at bay. Unfortunately the IMAPFilter version in Debian Jessie doesn't even support "dry run" (-n) which is not so cool when developing complex filter rules. So I backported the latest (sid) version and agreed with Sylvestre Ledru, one of its maintainers, to share it here and see whether making an official backport is worth it. It's a straight recompile so no magic and no source code or packaging changes required.

Get it while its hot:

imapfilter_2.6.11-1~bpo8+1_amd64.deb (IMAPFilter Jessie backport)
SHA1: bedb9c39e576a58acaf41395e667c84a1b400776

Clever LUA snippets for ~/.imapfilter/config.lua appreciated.

If you see Thunderbird hanging during startup for a minute and then continuing to load fine, you are probably running into an issue similar to what I saw when Debian migrated Icedove back to the "official" Mozilla Thunderbird branding and changed ~/.icedove to ~/.thunderbird in the process (one symlinked to the other).

Looking at the console log (=start Thunderbird from a terminal so you see its messages), I got:

console.log: foxclocks.bootstrap._loadIntoWindow(): got xul-overlay-merged - waiting for overlay-loaded
[.. one minute delay ..]
console.log: foxclocks.bootstrap._windowListener(): got window load chrome://global/content/commonDialog.xul

Stracing confirms it hangs because Thunderbird loops waiting for a FUTEX until that apparently gets kicked by a XUL core timeout.
(Thanks for defensive programming folks!)

So in my case uninstalling the Add-On Foxclocks easily solved the problem.

I assume other Thunderbird Add-Ons may cause the same issue, hence the more generic description above.

Netatalk 3.1.9 has been released with two interesting fixes / amendments:

• FIX: afpd: fix "admin group" option
• NEW: afpd: new options "force user" and "force group"

Here are the full release notes for 3.1.9 for your reading pleasure.

Due to upstream now differentiating between SysVinit and systemd packages I've followed that for simplicity's sake and built libgcrypt-only builds. If you need the openssl-based tools continue to use the 3.1.8 openssl build until you have finished your migration to a safer password storage.

Be sure to read the original blog post if you are new to Netatalk3 on Debian Jessie! You'll get nowhere if you install the .debs below and don't know about the upgrade path. So RTFA.

Now with that out of the way:

The Debian Netatalk3 saga continues at bug #685878. In season 4 of the epic the main issue still seems to be unclear license indications of a (very) few source files. And the usual "you go fix it", "no! you go fix it!". May be the fact that Firefox will be Firefox again in Debian [yeah!] could serve as an inspiration to the Netatalk maintainers?

Ah, well, until we have the eureka moment for Netatalk3 (4?) ...
<pragmatism style="priority-on-users:yes"> ... I'll post my .debs of the new 3.1.8 version of Netatalk as well.

Be sure to read the original blog post if you are new to Netatalk3 on Debian Jessie! You'll get nowhere if you install the .debs below and don't know about the upgrade path. So RTFA.

The release notes for 3.1.8 don't list anything that makes the update look mandatory but there is a nice compatibility fix for shares also exported via Samba (compatible xattrs handling). And it's faster.

The update instructions (assuming you have installed 3.1.7 before) are:

And here are the files:

Upgrading Debian 7 (Wheezy) servers to Debian 8 (Jessie) proves (unexpectedly) quite rough around the edges.

That's what you get for using a version x.0, we should have known better .

And - of course - the release notes follow the common practice of not even mentioning any of the issues we encountered so far.

Ah, well, let's go through the first one:

In Debian 7 (Wheezy) there was netatalk 2.2.2 (packages link). Now during upgrades that package may or may not get removed. There is no netatalk in Debian 8 (Jessie) anymore. Duh. There is in sid (aka Debian unstable) (packages link) so we may see a backport some time. Or not. In any case this is still 2.2.5 at the time of writing and as Adrian Knoth put it in the three year old bug asking for a upgrade to Netatalk 3:

Let's not ship another release without netatalk3, it's embarrassing.

Yes. It is. Removing a working version and not even mentioning it in the release notes is even worse though. So no cookies there.

Luckily the absolutely awesome Debian and greater FLOSS community have sorted 90% of the problem out for us already:

A quick Google search turns up an excellent article on netatalk's wiki that details installing Netatalk 3.1.7 on Debian 8 Jessie. There are two shortcomings to this: First it doesn't compile to .debs but installs besides apt and friends. And second it compiles with Spotlight search, courtesy of Gnome tracker, which doesn't really work well on servers yet. Hence we're lucky that Adrian Knoth's debified install has not yet added the tracker dependencies. It does compile for systemd use (the default for Debian 8 Jessie). If you want to continue using SysVInit, you need to modify debian/rules.

Compiling to .debs becomes as easy as:

This should leave you with (at the time of writing this):

Obviously you can download the files above if you run the AMD64 architecture and trust me enough to compile them for you.

The core team organizing DebConf, the annual Debian developer conference, reached out to me two weeks ago to help support this year's effort a bit.

I'm very happy to do so as Debian is a cornerstone of everything I do in the Open Source/Free Software space.

To get me started I got access to a lot of mailing lists and irc channels. And even more git repositories. So many that the DebConf team even has an instruction page on how the repositories all fit together.

It's unfortunately quite common to split a bigger project into many git repositories to ease access rights management and reduce the noise and data transfer volume for the average user. The downside is, everybody ends up with a dozen or more individual repositories to keep pulling. And then there's git annex for yet another level of indirection.

Joey Hess, a former Debian developer, has even written an extensive tool, myrepos, to meta-manage the different repositories and it can do quite some magic across different SCMSs¹. In my case this is a bit of an overkill though.

And using myrepos may get you confused at some point whether to now run mr or git directly for each batch of repos you have inherited over some time of working on multiple projects.² Thus I prefer the simple route:

Check out each repository into a common top-level directory (~/debconf/ in this case) and then put the following two lines into an executable script git_pull_all into that top level directory:

This will allow you to pull all git repos with one command and keep the normal syntax for everything else you do with each repo.

The --mindepth and --maxdepth will instruct find to just go and run your git pull only inside each direct child of the top level directory. So recursion depth = 1. That is the single trick there is to this.

Updates:

If you like to have some color and a bit of a spaced layout for improved readability, try:

When you have pull.rebase=true set in your .gitconfig, you can run ./git_pull_all --no-rebase to avoid rebases in case you work somewhere and want to have the merge commits.

P.S.: The DebConf15 Heidelberg registration just opened, please check the DebConf15 homepage for news, venue information and please register if you want to come around.