ftp.fau.de news and statistics

Problems with Opensuse Mirror

Fri, 17 Jul 2026 11:27:17 +0200

There are currently problems with our mirror of opensuse.

Since June 08, it has been having problems staying up-to-date.

This is caused by infrastructure problems on opensuses end - their main upstream server delivers abysmal transfer rates to us. Unfortunately, transfer rates of about 2 Megabytes per second are not really enough to keep in sync with the rate of changes that opensuse has.

We have tried to mitigate the situation by pulling updates from other sources, but these are incomplete.

Mirrors generating most traffic in 2025

Thu, 05 Feb 2026 12:00:00 +0200

The total outgoing traffic of ftp.fau.de increased from 10.06 PiB in 2024 to 10.22 PiB in 2025, a below-noise-level increase of only 1.5%.

Rank	Mirror	Traffic 2025 in TB	Rank/Traffic 2024 (for comparison)
1	mint/iso (Linux distribution, disc images)	1517	2 / 1381
2	kiwix (offline Wikipedia)	807	3 / 1106
3	almalinux (Linux distribution)	741	6 / 353
4	fdroid (Free and Open-Source Android app repository)	669	1 / 1794
5	cdn.media.ccc.de (recordings of IT-related events)	651	8 / 273
6	opensuse (Linux distribution)	592	5 / 354
7	gimp (Free and Open-Source image manipulation program)	541	15 / 203
8	fedora (Linux distribution)	510	4 / 438
9	macports	383	9 / 263
10	rockylinux	382	18 / 182

The percentage of IPv6 traffic increased marginally to 30% (3.02 PiB), after 29% in 2024, 26% in 2023, 26% in 2022, 27% in 2021, 27% in 2020, 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2024

Wed, 04 Feb 2026 15:21:00 +0200

The total outgoing traffic of ftp.fau.de increased from 8.51 PiB in 2023 to 10.06 PiB in 2024, an increase of only 18%.

Rank	Mirror	Traffic 2024 in TB	Rank/Traffic 2023 (for comparison)
1	fdroid (Free and Open-Source Android app repository)	1794	1 / 1639
2	mint/iso (Linux distribution, disc images)	1381	2 / 1040
3	kiwix (offline Wikipedia)	1106	3 / 1021
4	fedora (Linux distribution)	438	5 / 456
5	opensuse (Linux distribution)	354	7 / 244
6	almalinux (Linux distribution)	353	28 / 66
7	epel (Extra Packages for Enterprise Linux)	282	12 / 192
8	cdn.media.ccc.de (recordings of IT-related events)	273	26 / 77
9	macports	263	27 / 68
10	ubuntu	259	11 / 200

The percentage of IPv6 traffic increased slightly to 29% (2.88 PiB), after 26% in 2023, 26% in 2022, 27% in 2021, 27% in 2020, 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2023

Wed, 04 Feb 2026 14:45:00 +0200

The total outgoing traffic of ftp.fau.de increased from 6.57 PiB in 2022 to 8.51 PiB in 2023, an increase of 30%.

Rank	Mirror	Traffic 2023 in TB	Rank/Traffic 2022 (for comparison)
1	fdroid (Free and Open-Source Android app repository)	1639	4 / 494
2	mint/iso (Linux distribution, disc images)	1040	1 / 1075
3	kiwix (offline Wikipedia)	1021	3 / 726
4	centos (Linux distribution)	853	2 / 780
5	fedora (Linux distribution)	456	6 / 293
6	qtproject (Qt Toolkit)	261	5 / 295
7	opensuse (Linux distribution)	244	7 / 270
8	gimp (Free and Open-Source image manipulation program)	230	10 / 173
9	lineageos (Free and Open-Source Android distribution)	217	9 / 189
10	eclipse	215	8 / 238

The percentage of IPv6 traffic stagnated at 26% (2.23 PiB), after 26% in 2022, 27% in 2021, 27% in 2020, 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2022

Mon, 06 Feb 2023 16:36:00 +0200

The total outgoing traffic of ftp.fau.de increased from 5.04 PiB in 2021 to 6.57 PiB in 2022, an increase of 30%.

Rank	Mirror	Traffic 2022 in TB	Rank/Traffic 2021 (for comparison)
1	mint/iso (Linux distribution, disc images)	1075	1 / 849
2	centos (Linux distribution)	780	10 / 160
3	kiwix (offline Wikipedia)	726	2 / 519
4	fdroid (Free and Open-Source Android app repository)	494	3 / 304
5	qtproject (Qt Toolkit)	295	4 / 275
6	fedora (Linux distribution)	293	8 / 186
7	opensuse (Linux distribution)	270	9 / 175
8	eclipse	238	7 / 193
9	lineageos (Free and Open-Source Android distribution)	189	6 / 199
10	gimp (Free and Open-Source image manipulation program)	173	5 / 266

The percentage of IPv6 traffic dropped slightly, it is now at 26% (1.68 PiB), after 27% in 2021, 27% in 2020, 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2021

Mon, 14 Feb 2022 10:46:01 +0200

The total outgoing traffic of ftp.fau.de increased from 4.12 PiB in 2020 to 5.04 PiB in 2021, an increase of 22%.

Rank	Mirror	Traffic 2021 in TB	Rank/Traffic 2020 (for comparison)
1	mint/iso	849	2 / 389
2	kiwix (offline Wikipedia)	519	1 / 538
3	fdroid (Free and Open-Source Android app repository	304	5 / 242
4	qtproject (Qt Toolkit)	275	4 / 356
5	gimp	266	3 / 376
6	lineageos (Free and Open-Source Android distribution)	199	6 / 204
7	eclipse	193	- / 99
8	fedora	186	8 / 148
9	opensuse	175	10 / 108
10	centos	160	7 / 159

The percentage of IPv6 traffic stagnated, with 27% (1.36 PiB), after 27% in 2020, 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2020

Mon, 14 Feb 2022 10:44:00 +0200

It seems that I have not posted the traffic stats for 2020 yet. Well, better late than never, so here they are.

The total outgoing traffic of ftp.fau.de increased from 3.52 PiB in 2019 to 4.12 PiB in 2020, an increase of 17%.

Rank	Mirror	Traffic 2020 in TB	Rank/Traffic 2019 (for comparison)
1	kiwix (offline Wikipedia)	538	2 / 458
2	mint/iso	389	3 / 260
3	gimp	376	- / 1
4	qtproject (Qt Toolkit)	356	1 / 511
5	fdroid (Free and Open-Source Android app repository	242	11 / 109
6	lineageos (Free and Open-Source Android distribution)	204	4 / 246
7	centos	159	9 / 117
8	fedora	148	7 / 136
9	videolan	114	- / 97
10	opensuse	108	6 / 138

The percentage of IPv6 traffic increased a tiny bit again, to 27% (1.13 PB), after 25% in 2019, 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Unplanned Outage on June 03 [solved]

Thu, 04 Jun 2020 20:40:00 +0200

On June 03, 2020, at around 16:15 local time (14:15 UTC), disk accesses on ftp.fau.de became extremely slow. Less than an hour later, any attempts to access the disks with the ftp-data on it failed. Investigation revealed that the big RAID controller that manages all the external disk enclosures for the data had stopped responding completely. While the failed controller could temporarily be brought back by a powercycle at around 18:00 local time (16:00 UTC), it failed again within 10 minutes of booting the machine. Unfortunately, there was no compatible replacement for the failed controller onsite. A replacement has been ordered and shipped, but has not arrived yet. As all parcel services are severely overloaded due to the Corona crisis, it is currently unclear when it will arrive.

Mirrors generating most traffic in 2019

Thu, 20 Feb 2020 14:17:00 +0200

The total traffic of ftp.fau.de increased from 3.22 PB in 2018 to 3.52 PB in 2019, an unusually small increase of only 9%.

Rank	Mirror	Traffic 2019 in TB	Rank/Traffic 2018 (for comparison)
1	qtproject (Qt Toolkit)	511	2 / 445
2	kiwix (offline Wikipedia)	458	1 / 476
3	mint/iso	260	5 / 255
4	lineageos (Free and Open-Source Android distribution)	246	3 / 327
5	eclipse	162	4 / 266
6	opensuse	138	7 / 119
7	fedora	136	6 / 137
8	cdn.media.ccc.de (Talk recordings from CCC and related conferences)	120	- / 94
9	centos	117	9 / 109
10	osmc (Open Source Media Center)	112	8 / 113

The percentage of IPv6 traffic increased a tiny bit again, to 25% (0.87 PB), after 22% in 2018, 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors Generating Most Traffic in 2018

Mon, 23 Sep 2019 13:47:00 +0200

The total traffic of ftp.fau.de increased from 2.51 PB in 2017 to 3.22 PB in 2018, a 28% increase.

Rank	Mirror	Traffic 2018 in TB	Rank/Traffic 2017 (for comparison)
1	kiwix (offline Wikipedia)	476	1 / 371
2	qtproject (Qt Toolkit)	445	2 / 274
3	lineageos (Free and Open-Source Android distribution)	327	3 / 203
4	eclipse	266	7 / 147
5	mint/iso	255	5 / 190
6	fedora	137	8 / 103
7	opensuse	119	5 / 152
8	osmc (Open Source Media Center)	113	6 / 149
9	centos	109	11 / 69
10	ctan (comprehensive TEX archive network)	95	10 / 93

Even though the absolute amount of IPv6 traffic increased a bit, its percentage of all traffic stagnated, with 22% (0.72 PB) in 2018, after 22% in 2017, 14% in 2016 and 11% in 2015.

Mirrors generating most traffic in 2017

Mon, 22 Jan 2018 12:06:00 +0200

The total traffic of ftp.fau.de increased from 1.89 PB in 2016 to 2.51 PB in 2017, by 33%. 203 TB alone was accounted to one of our newest additions from late may 2017: lineageos, a free and open-source android distribution and successor of cyanogenmod (which was discontinued).

Rank	Mirror	Traffic 2017 in TB	Rank/Traffic 2016 (for comparison)
1	kiwix (offline Wikipedia)	371	2 / 262
2	qtproject (Qt Toolkit)	274	1 / 264
3	lineageos (Free and Open-Source Android distribution)	203 (since late may)	- / -
4	mint/iso	190	5 / 134
5	opensuse	152	4 / 145
6	osmc (Open Source Media Center)	149	3 / 172
7	eclipse	147	6 / 131
8	fedora	103	7 / 115
9	cdn.media.ccc.de (Talk recordings from CCC conferences)	99	8 / 91
10	ctan (comprehensive TEX archive network)	93	9 / 76

The total IPv6 traffic increased significantly, to 22% (0.55 PB) of all traffic in 2017, from 14% in 2016 and 11% in 2015.

Downtime on January 12

Fri, 12 Jan 2018 12:00:00 +0200

We had a little downtime today between around 12:10 and 13:20. About 5 minutes of this downtime were planned - we simply wanted to reboot the machine. Unfortunately, the machine did not come back up after the reboot, and it took a while to figure out what the problem was.

As it turns out, the machine was unable to mount the huge volume with all our mirrors on it during boot. Manually mounting the disk failed as well because the device just wasn’t there. In lvdisplay the volume was listed as unavailable, and trying to set it available with lvchange failed with the message /usr/sbin/cache_check: execvp failed: No such file or directory Check of pool bigdata/ftpcachedata failed (status:2). Manual repair required!

Experiments with LVM-cache

Sat, 30 Sep 2017 10:11:00 +0200

Recently, we’ve frequently reached the I/O capacity of our RAID array during peak hours, meaning that increasingly often downloads were not limited by network speed, but by how fast our disks could deliver the data.

While we use a hardware RAID6 which does deliver pretty decent read speeds, we’re still using traditional magnetic hard drives, not SSDs. While these arrays easily deliver more than a Gigabyte per second when reading sequentially, this performance drops rapidly the more random the I/O gets, i.e. the more different files are requested at the same time. Of course, due to the nature of our FTP, which provides mirrors for a whole bunch of different projects, we do get a large amount of random I/O.

Mirrors Generating Most Traffic in 2016

Sun, 16 Apr 2017 12:00:00 +0200

It seems I haven’t posted the traditional annual mirror stats for 2016 yet. Well, lets fix that: Here are the most used mirrors on ftp.fau.de in 2016:

Rank	Mirror	Traffic 2016 in TB	Rank/Traffic 2015 (for comparison)
1	qtproject (Qt Toolkit)	264	1 / 199
2	kiwix (offline Wikipedia)	262	2 / 179
3	osmc (Open Source Media Center)	172	- / 35
4	opensuse	145	4 / 139
5	mint	134	3 / 179
6	eclipse	131	6 / 97
7	fedora	115	5 / 100
8	cdn.media.ccc.de (Talk recordings from CCC conferences)	91	7 / 83
9	ctan (comprehensive TEX archive network)	76	8 / 63
10	tdf (The Document Foundation - LibreOffice)	58	9 / 48

Comparing this list to last year, the first thing one notices is the new entry on rank 3: OSMC generates a steady amount of traffic, with visible peaks whenever they do a release. They were not in the 2015 top ten because we only started mirroring it in Q4 of 2015.

Evaluating Project Mirroring by Cost vs Profit

Mon, 11 Apr 2016 12:00:00 +0200

People operate mirrors out of different reasons, this could be purely altruistic to support open source communities, or to reduce incoming traffic by providing local clients with an internal package source, or to tilt the in/out ratio of the internet uplink. What ever the reasons are, they are all associated with the usage of outbound traffic and local storage size, in addition to occupation of other hardware and administrative resources. We will consider traffic and storage requirements as the costs and outgoing traffic as the profit (to the general public or an organization) a mirror service provides.

Mirrors generating most traffic in 2015

Wed, 03 Feb 2016 12:00:00 +0200

Here are the most used mirrors in 2015:

Rank	Mirror	Traffic 2015 in TB	Rank/Traffic 2014 (for comparison)
1	qtproject (Qt Toolkit)	199	1 / 172
2	kiwix	179	- / 0
3	mint/iso (Linux Mint ISOs)	177	10 / 31
4	opensuse	139	2 / 106
5	fedora	100	6 / 44
6	eclipse	97	4 / 86
7	cdn.media.ccc.de (Talk recordings from CCC conferences)	83	8 / 32
8	ctan (comprehensive TEX archive network)	63	7 / 40
9	tdf (The Document Foundation – LibreOffice)	48	5 / 48
10	videolan	40	3 / 88

Kiwix on rank 2 has only been mirrored since March 2015, so it generated that amount of traffic in only 9 and a half months - it might well take over the top spot next year. The Ubuntu release ISOs dropped out of the Top 10 for IPv4. As is to be expected, the CCC conference recordings generate extremely peaky traffic after CCC events - setting a new record high with 11.3 TB in just one day on December 30 (after 32C3). It might even have made a little bit more, but unfortunately the webserver ran out of threads because someone apparently distributed web-torrent-files with 64 KB of chunksize.

Changing Filesystems: from XFS to EXT4

Mon, 15 Jun 2015 12:00:00 +0200

Since we moved the ftp to the (then) new hardware in October 2013, we had been using XFS as the filesystem on which we store all our mirror trees. All data resided in one single large XFS filesystem of 35 TB. That worked rather well until we updated the operating system on the machine in January.

After the update, the machine behaved extremely unstable - and in crass contrast to its 460 days uptime before the update. Sometimes all file I/O would stop for a few minutes (up to 30), and then suddenly continue as if nothing had happened. Those hangs happened in average twice a day. Sometimes the machine would also lock up completely and need to be reset. During the hangs, the machine would log many of the following error-messages to the kernel log:

Mirrors generating most traffic in 2014

Wed, 18 Mar 2015 12:00:00 +0200

While we publish daily stats for all of our mirrors at https://ftp.fau.de/cgi-bin/show-ftp-stats.cgi, there is currently no aggregation over a whole year. So here are the most used mirrors over the whole year:

Rank	Mirror	Traffic 2014 in TB
1	qtproject (Qt Toolkit)	172
2	opensuse	106
3	videolan	88
4	eclipse	86
5	tdf (The Document Foundation - LibreOffice)	48
6	fedora	44
7	ctan (comprehensive TEX archive network)	40
8	cdn.media.ccc.de (Talk recordings from CCC conferences)	32
9	ubuntu-releases (Ubuntu CD Images)	32
10	mint/iso (Linux Mint ISOs)	31

The list is slightly different for IPv6.

Experimental GeoIP statistics

Sat, 08 Nov 2014 12:00:00 +0200

Since the beginning of September, we’ve been creating experimental GeoIP-statistics to see where the users of ftp.fau.de come from. We’re drawing nice maps from the results. You can find these stats from our general ftp statistics page - for days where GeoIP-stats are available, you will find a link to them at the bottom of the page. Here is an example:

As you can see, unsurprisingly most of our users come from Germany. Besides the map there is also a table that show the respective percentages per country - in the map above, Germany accounts for about 50 percent of all accesses. Note that is counting the number of bytes transferred, not the number of accesses.

New Mirrors in the last months

Thu, 19 Dec 2013 12:00:00 +0200

Over the last 2.5 months we have added a few new mirrors. Amongst those are:

CCC conference recordings by FeM. Here you can find recordings of almost all talks from the yearly Chaos Communication Congresses. This mirror also takes part in their official mirror network for these recordings under http://mirror.fem-net.de/CCC/
CentOS. CentOS is a free rebuild of the Redhat Enterprise Linux packages (without the support of course).
Eclipse, an IDE
EPEL, Extra Packages for Enterprise Linux - EPEL packages a lot of additional software for Redhat Enterprise Linux or its clones
the Qt project. It develops Qt, which is a great multiplatform application framework. There is a commercial company backing the project (currently Digia) that also offers commercial variants of the framework. Only the non-commercial releases are distributed over the mirror-network in which we're taking part here. This is now one of the three mirrors that causes the most traffic on our FTP.
The Document Foundation - TDF is responsible for the development of LibreOffice
Trinity Desktop Environment. The TDE project is a fork of KDE3 and continues to develop a productive desktop environment that does not put looks above functionality.
the VideoLAN project, which produces amongst other things a great free media player that plays almost everything (VLC media player). This is now another one of the three mirrors that causes the most traffic on our FTP.
XBMC, a free media center software

More Statistics

Wed, 20 Nov 2013 12:00:00 +0200

We have improved the publicly available statistics for our FTP server. You can now see how much traffic each individual mirror makes, and how much of the traffic was IPv6 vs. IPv4. The statistics are available at https://ftp.fau.de/cgi-bin/show-ftp-stats.cgi.

With this, you can see for example that the latest OpenSuSE 13.1 release had a quite significant impact on our FTP: The statistics for 19. November 2013 show that we distributed almost 9 TB for opensuse on that day, more than 5 times the traffic of all other mirrors combined.

New FTP server

Tue, 01 Oct 2013 12:00:00 +0200

From this morning (October 01) on, ftp.uni-erlangen.de and ftp.fau.de point to new hardware.

The new machine is much more powerful than the old one, and we tried our best to make the mirroring setup as robust as possible. Hopefully, incosistent and outdated mirrors (because the mirror-job hung) are now a thing of the past. You can actually check this yourself: The FTP startpage lists the last successful run for all major mirrors, and there is also a page that shows how long the last mirror runs took and if they succeeded or not.

Abkündigung privater Dateiaustauschbereiche

Thu, 29 Aug 2013 12:00:00 +0200

(note: this post is the only german post in this blog. We generally switched to english after that.)

ftp.fau.de / ftp.uni-erlangen.de wird derzeit auf einem neuen, deutlich leistungsfähigeren System neu aufgesetzt. Damit wollen wir diesen beliebten Dienst auf eine solide Basis für die kommenden Jahre stellen. Mit dem neuen System verschwindet aber auch ein Dienst. In der Vergangenheit gab es auf ftp.uni-erlangen.de neben den öffentlichen Mirrors für zahlreiche Linux-Distributionen und andere Open-Source-Software einige wenige “private Dateiaustauschbereiche”: Benutzer konnten sich mit Benutzernamen und Passwort einloggen und landeten dann in einem geschützten Bereich. Darüber war z.B. der Austausch von Dateien die zu gross fuer einen eMail-Anhang sind mit externen Projektpartnern möglich. Dieser Dienst wird auf dem neuen System nicht mehr eingerichtet und somit zum 01.10.2013 ersatzlos eingestellt werden.