CUCC Expedition Handbook

Expo computing setup

If the internet is not working, the first thing to check is that
the black WiFi antenna is still upright and has not been knocked sideways.

Since 2018 we now have proper internet access in the tatty hut so the set-up on expo is exactly the same as the rest of the year. An Expo laptop is also provided, but you should be able to use your own computer in exactly the same way (if you brought one) as you do at home.

We have our own WiFi ("tattyhut" and usual cavey:beery password) which is connected (deviously) to the Gasthof campsite WiFi. So please don't stream video or do a lot of operating system updates using it as the Gasthof is probably paying per GB to their supplier.

Two WiFi systems

Our own Wifi only works very close to the tatty hut. If you are camped over the road near the Gasthof you will need to use the Gasthof WiFi 'staudnwirt'. This takes you to a login page on a web browser and it will log you out if you stop using it or whenever it thinks you have been on too long. Get instructions from the Gasthof campsite reception.

Expo laptop

The Expo laptop 'debian' in the tatty hut is a Dell Latitude E4200 laptop (on loan from Philip Sargent) which is connected to the router by a cable and also by WiFi (it's wifi configuration was fixed by Sam in 2019). It also has an external numberpad as a couple of vital keys are dead (e.g. down-arrow). It runs Linux (debian) and has installed all the software for talking to the server for:

Any laptop or phone can connect to the server via the "tattyhut" WiFi and, with some configuration, can be set up to do all those things too. New expoers are advised to use the Expo laptop first to see how it all works.

The laptop is usually connected to an extra LCD screen so that you can see surveys more easily as the laptop itself is small.

Either the Expo laptop or your own laptop will use the version control system to synchronise cave data. It's easier to use the Expo laptop as the software is already set up. But if you set up your own computer then you will get a more familiar environment. See the Expo Online Systems Manual for info on how to do that.

Through the miracle of the distributed version control system, everyone can edit the data on multiple laptops at the same time and it should all get merged.

At the end of expo we don't need to bring the Expo laptop back back to the UK (though we will, as we will want to do operating system updates during the year and maybe fix that keyboard) as all the caving data updates are continuously synchronised with the public server during the expo.

Printing and Scanning

We have A4 printer and scanner attached via usb cables and a usb hub to the Expo laptop. In 2018 we also connected the printer to the router with an ethernet cable and this made things more reliable. Configuring the scanner to be used via WiFi is yet to be done, but the printer is "shared" by the Expo laptop and so canbe used by any laptop. (The printer has WiFi itself and so should be useable directly but we haven't got this configured properly yet.) Use a usb stick to transfer files for printing if you can't get your own laptop or phone to work with the printer.

The Expo Laptop's Friend: Aziraphale

In 2019 we had another general-use laptop. This is not connected by any cabling and just uses WiFi. Like the expo laptop it is running debian Linux and has the same set of software installed (survex/aven, tunnelx, therion, git etc.) and you login to it using the username "expo" and the usual cavey:beery password. It is a 14-inch Thinkpad on loan from Michael Sargent and it is called "aziraphale". The expo laptop is just called "debian".

Networking Hardware - experts only

The networking hardware is an Acer Aspire netbook which keeps us logged in to the Gasthof and does firewalling to provide local connectivity and local WiFi. The antenna which we use to connect to the Staudnwirt WiFi is a ~32cm long black stick mounted on a small shelf high above the sink/stove area and connected via a usb cable to the Acer netbook. There is no separate router: it is all done by the Acer notebook.

The potato hut WiFi is running DHCP and allocating IP addresses of the form 192.168.1.x where x is a number between 11 and 99 .

The Expo laptop has a dynamic local address of this form. It has a 64GB microSD card plugged into it which holds the local copy of /expofiles/ .

The Acer Aspire netbook ("tclaspire3") is on a static address

The Gasthof WiFi - which you can still use - is "StaudnGast" and has no WiFi password but there is a login webpage (Gast/Gastin21). It allocates IP addresses in the range 192.168.2.x etc. The antenna is now on the first-floor balcony within sight of the tatty hut window.

The Acer Aspire is on on WiFi. This is the address to use for configuring it using ssh when everything else has failed. So to manage the connection to the Gasthof WiFi you would use

ssh expo@
to run Mark Shinwell's script (re-edited by Sam 2019)
This typically needs to be run once or twice a day when the internet stops working. Sometimes you have to walk over to the blue laptop and run this script directly by typing on its keyboard as the network has collapsed so badly that ssh doesn't work.

The Acer netbook needs to have its persistent networking set up correctly in addition to the script. This is the wicd gui program that has an icon in the top-right of the sceen in the system panel. (Or search in all applications in the Internet section for the wicd application). Set the checkboxes so that the Acer does connect to any network except the Staudingast wifi network, and also tick the 'automatica;lly reconnect' checkbox for the "StaudnGast" network.

Historical Note

Prior to 2018 we used to run an unconnected local network with our own DNS domain name "potato.hut", our own server holding all the website and survey data, and published WiFi as SSID "tattyhut". Updates to the rest of the world were done by taking an up-to-date laptop which had been in the tatty hut to a real internet connection and pushing the changes to the distributed version control system on to be merged.

In 2017 the hard-drive on our server died which triggered the general reconfiguration to connect the tattyhut to the internet continuously and not to have our own local server. This coincides with a much-improved WiFi service at the Gasthof in recent years.

Go on to: Expo online systems