on Muenzgasse 7 has been shown as offline since last night.
So far, no one has contacted us. We are preparing to upgrade the building to Gigabit. (12:00)
3 PM: No power, no internet. We upgraded the hardware. As soon as the power is back on you got gigabit internet.
on As announced on January 13, we are now using our standard configuration on Konrad-Adenauer-Strasse, after extending it for an additional month.
The change will prevent access points, repeaters, and incorrectly configured routers from using up too many IP addresses, which can deny other residents access to the internet.
Instructions on how to configure routers can always be found in our tutorials.
on On Thursday, April 18, starting around 6:30 PM, we will finally be able to equip our dormitories in Viktor-Renner-Straße with more modern technology.
For the residents, this means they will be able to use gigabit internet in their rooms afterwards.
For us as Netz-AK the upgrade also brings us major advantages in the management of our network. The switches that were previously installed in Viktor-Renner-Straße are the very last to not support various standard features and needed to be configured very differently from the rest of our infrastructure, hindering any automation efforts.
We expect the installation to take about 3 hours, meaning you will probably have unrestricted internet access again from 9:30 PM.
Update 2024-04-23: After we were initially only able to replace the switches at Viktor-Renner-Straße 2 last Thursday, we have completed all maintenance work at 4 today. If you still have problems with your internet, please contact us individually using our contact form! This is the only way we can identify the individual problems and help you effectively, because the sources of error can be very different.
As everywhere else in our network, the maximum number of IP addresses assigned in Viktor-Renner-Straße is now basically limited to 1 per connection. However, you don’t have to buy a new router now if, for example, you have previously operated a WiFi repeater and therefore need several IP addresses. For all such connections that we could identify, we have temporarily relaxed this restriction. Let us know if we missed one.
on 
Imagine you’re living in a student dorm that has had fiber optic since 1974. And then, in 2024, you suddenly get an advertisement for the “soon arrival of fiber optic” in your mailbox.
Great!
If everything goes well, by this year, every room will be equipped with a synchronous gigabit connection, meaning 1,000 megabits of both upload and download.
That’s at least our goal for the 20th anniversary of our Network Work-group
on In week 3, which is from January 15 to January 21, some maintenance work is scheduled.
The maintenance work starting on Friday will be long and unpleasant for the people in Hohenheim.
The fiber optic lines in Hohenheim to get extended to be used in a different location because of the renovations.
Without the fiber optic line, there will be no internet there.
The work will be carried out by a specialist company and is scheduled to start on Friday morning, which is January 19.
The work will take a long time, so we announce a complete internet outage in all student dormitories in Hohenheim from Friday morning to Saturday noon.
If it’s done faster, please avoid sending us messages all day. It won’t speed things up.
The company will complete their work as quickly as possible, and we will reconnect the fiber optics.
On Thursday, January 18, starting around 5:30 PM, we will finally be able to equip our dormitories in Konrad-Adenauer-Strasse with modern technology.
For the residents, this means they will be able to use gigabit internet in their rooms afterwards.
Since we haven’t been able to implement the exclusive use of routers in Konrad-Adenauer-Strasse due to technical reasons, we will not enforce this immediately but only from the start of the summer semester (April 1, 2024).
We expect the installation to take about 3 hours, meaning you will probably have unrestricted internet access again from 9:00 PM.
There will be a maximum half-hour interruption in internet access at the Schimpf-WG. We had announced this work several times before but could never implement it due to problems accessing our hardware in the neighboring building. We cannot say exactly when this will be, but it will happen some evening between Monday and Thursday.
on The rooms at Schimpf Eck (at Lustnauer Tor 1) now all have network sockets!
The only thing left to connect you to the dorm’s fiber-optic network is to lay down the fiber-optic cables. We’ll figure out who’s doing it and how it’s done. In the meantime, there’s a wireless connection.
The construction work for a proper wireless operation should be finished in November. Until then, we have a temporary solution for you.
We are working on getting everything done in September, so you can have some internet by the time the semester starts.
on Surprisingly, construction work for Schimpf started last week. Each room, as usual in our dormitories, will have its own network connection with a double network socket, and one connection will be active.
We don’t consider a comprehensive alternative like WLAN networking, which is often desired, to be practical here. Those who have dealt with connecting hundreds of devices to Eduroam will understand why we are avoiding it.
In each room, you can set up your own secure and easy-to-configure WLAN with a simple router for around €35, allowing you to connect everything from a printer to a PlayStation.
The connection of the WG units in Schimpf Eck depends on the work at Pfleghof, whose starting date is still unknown to us. As surprises are possible, we prefer not to estimate when it will be ready. Getting new DSL contracts doesn’t seem sensible to us. We hope that the WG units will find a fair solution to redistribute the internet access costs or find a way to get rid of these contracts once the dormitory is stably connected to our network.
The final connection via fiber optic to our network is planned but not yet confirmed.
on Good morning dear Hohenheim residents!
Today, the Uplink upgrade will be fully implemented. If everything goes well, you will be running on 10G afterwards, and the outages will come to an end.
To transport the Uplink technology from the temporary location at Schwerzstraße 2 to the new location at Egilolfstraße 57, we will need some time. Unfortunately, during this time, the Hohenheim dormitories will be offline.
Since we have to unplug the device and then reconnect it in a different building, it cannot be avoided. However, we will hurry as much as possible.
on It’s time!
Last night, we were given the task to carry out the upgrade.
As mentioned before, we had already prepared a new location for the uplink, which will enable all Hohenheim residences to go online.
To transport the uplink technology from the temporary location at Schwerzstraße 2 to the new location at Egilolfstraße 57, we will need some time. During this time, the residences in Hohenheim will unfortunately be offline.
Since we need to disconnect the device and then reconnect it in a different building, it cannot be avoided. However, we will do our best to expedite the process.
The estimated duration will probably be around one to two hours this afternoon, with several short outages as we make the necessary adjustments throughout the day, starting in the morning.
We will update this post once we have more information.
on Please fix the fucking network. There are so many problems with it. Impossible…
Unknown author, Hohenheim 13.05.23 –
We have been receiving emails like this in the past few days. It’s understandable, considering the outages we’ve had in the past week, turning Hohenheim into an internet wasteland. Believe us, we want nothing more than to have the finest internet flowing through the fiber optics. However, let’s take a look at why it’s sometimes not that simple.
First, let’s provide an overview of the locations in Hohenheim:
23 buildings
50 Layer-2 switches
1660 connections in the user network
2x 1 Gbps uplink towards the student union
As you can see, currently, all the connections converge at Schwerzstrasse 1 and then split into two lines towards the student union.
Line 1: Egilolfstrasse 49, 51, 53, 57, 59; Fruhwirthstrasse 3-13; Welfenstrasse 80; and Chausseefeld 1-9.
Line 2: Egilolfstrasse 41, 43, 45; and Schwerzstrasse 1-3.
Both lines are equally loaded.
That’s the infrastructure setup.
Timeline:
In early April, we were requested to provide internet to Schwerzstrasse 3, which had been renovated and is now available as a dormitory.
During the initial inspection, we were informed that Schwerzstrasse 2 would undergo major renovation and the power would be shut off there.
At that time, Schwerzstrasse 2 still housed the uplink for the entire Hohenheim, and that required power. So, it was planned to move that hardware to Schwerzstrasse 3 on the same day. Fiber optics between the buildings are available and can be used.
April 19, 2023
We drive towards Schwerzstrasse 2 to check if there are enough lines to move the uplink towards Schwerzstrasse 3. We find a chaos of fiber optics and start taking notes.
According to the notes, everything should be fine, except for the shortage of cables. Ancient plug connections were used for the fiber optics.
April 24, 2023
We took time off to tackle the cabling in the new dormitory.
We arrived at 2 p.m. and immediately started equipping the new cabinet.
However, we encountered the first problem during the reconstruction of the uplink. The individual ports towards Stuwe remained offline. A measurement revealed that the attenuation was too high. You can imagine it as stuffing cotton in your ears. You hear much less and don’t understand everything.
The same applies to light; the further away or worse the material, the less you can see. That’s why many front doors have frosted glass. Light enters, but you can only see a little from the other side.
We suspect that the fiber optic between Schwerz.3 and Schwerz.1 might be defective or contaminated, acting like frosted glass.
As a result, we installed the uplink in Schwerz.1 to mitigate this attenuation. However, only one of the two lines came online there as well. We started trying different lines between Schwerz.1 and Schwerz.2 and eventually found at least 2 out of 24 fibers where the switch received enough information to provide a bit of internet.
That should be sufficient for one night, and we returned to Tübingen. Departure at 7 p.m.
April 25, 2023
Since we couldn’t find any documentation regarding Hohenheim in our records (at least the previous responsible person didn’t leave any), we went to Hohenheim with pen and paper in hand.
We diligently conducted measurements and discovered that the damaged line must be between Schwerz.2 and the university’s data center.
The staff at the data center were very helpful and showed us the relevant fibers and a switch, which belonged to Stuwe. We included it in our documentation. However, we don’t have access to it, so we couldn’t perform much diagnosis.
As a precaution, we replaced the fiber optic cable in the data center. We also noticed on a map in the machine room that there must be another building between the university and Schwerzstrasse. We headed there but unfortunately didn’t find anyone available.
Disappointed, we replaced a few more fiber cables in the patch panel of Schwerzstrasse 2 with higher-quality ones, hoping to improve the poor connection. Departure at 6 p.m.
April 26, 2023
We drove back, this time to the mysterious Building 1.21. In the basement, we found a cabinet with our fibers. We replaced the connecting cable between the panels in the cabinet and headed towards the university. However, the attenuation was still the same. Cleaning the fiber optics didn’t yield any results, so we switched to another fiber to rule out any faults. Unfortunately, it didn’t work at all.
We dismantled everything and drove back to Tübingen since the shared car reservation was only for 5 hours, and we had already spent 4.5 hours there.
We returned in the evening to continue the troubleshooting. Since the lines worked fine in Schwerzstrasse 2, we installed a homemade amplifier solution until we could reach the data center again. Departure at 9 p.m.
April 27, 2023
Early in the morning, we headed straight to the data center. By now, we had become adept at pleading for entry, and we replaced the fiber optics with another pair. Then we proceeded towards Emil-Wolf-Strasse (Building 1.21) and made the necessary connections. Lo and behold, the attenuation value improved from -23 dBm to a fantastic -7 dBm (significantly better).
The patch cable for Egilolfstrasse 45 had a bend and, lacking a better replacement, we substituted it with a multimode fiber (not ideal). Will it work? We quickly documented the changes and headed home. Departure at 4 p.m.
April 28, 2023
Disappointment struck. The uplink was now running smoothly, but Egilolfstrasse 45 seemed to be causing problems. We returned and replaced the multimode patch cable with a single-mode cable. From that point on, things started working smoothly again, and we happily returned home.
May 5, 2023
All the residents from Schwerzstrasse 2 have now moved to Schwerzstrasse 3. We noticed that four rooms were not properly patched (apologies for the mix-up!). We went there and corrected the connections. From Schwerzstrasse 2, we removed the equipment from the floors before the major renovation began. It was quite eerie there, but it seemed like there had been a good party.
May 7, 2023
Initial reports of disruptions in Egilolfstrasse 53-59. Evening outages were observed. We discovered numerous errors in the log. We went there in the evening and replaced the module at the switch (those things keep breaking).
May 8, 2023
Under load, especially in the evenings, we noticed an increasing number of errors. As a result, the traffic briefly decreased and then recovered. You may have experienced internet outages, but we noticed them through the error counter:
Receive:
Error Frames: 227,636,249
Transmit:
Error Frames: 0
Both of these values should be 0. It seems that either the fiber or the module is faulty.
Once again, we visited the location and swapped the fiber to eliminate it as a potential issue. However, we still encountered the same problem.
Two tests are pending:
We sent an email to the responsible person since we cannot access external hardware.
May 12, 2023
We received a response from the responsible person at Stuwe.
The examination and, if necessary, replacement will be carried out by the HEDV as part of the uplink expansion. However, the uplink expansion can only take place after the work on Schwerzstrasse 2 is completed.
According to his opinion, the uplink switch needs to be moved to another building, but which building is still uncertain. Until then, everything will remain as is.
Unfortunately, the responsible person will not be available on Friday.
That’s the summary of the events in the past few weeks.
Tomorrow, we will make another round of calls and try to find a solution with the responsible person, if they are available. We are just as frustrated as you are, and we are doing everything we can to provide you with a good internet connection. However, as you can see, sometimes it’s not just technical issues that are at play.
As soon as we have any new updates, we will notify you here.
Until then, have a pleasant evening!