LUCI Troubleshooting

This covers some LUCI problems that commonly arise when observing with the LUCI instruments.

Re-establishing the LUCI connection to the TCS (ICE connection to IIF)

The LUCI instruments need a connection with the TCS. This connection is made via the "ICE" software package and it connects the instrument to the IIF subsystem. If the IIF is restarted, any existing ICE connections to it are lost and are no longer usable. The same is true if the whole TCS is restarted. In those cases you will have to re-establish a connection as described below.

If there is no usable connection to the IIF, the LUCI log messages will show error messages complaining about not being able to talk to the telescope. They will occur when the instrument tries to save data (it needs information from the TCS to save in the FITS header), or when the instrument is reconfigured or periodically when instrument temperatures are read and then written to the TCS Data Dictionary. If the LUCI Telescope GUI is opened, the error messages will occur about once per second as it tries to get data to update its display.

There are 2 ways to re-establish communication between LUCI and the TCS. The first one to try is to use the "Telescope GUI" because it is the easier way. The second is to stop and restart the TelescopeService and the DataDictionaryConnector (see below).

To open the Telescope GUI, open a LUCI Management Console using the luci_console command. Look for the "TelescopeService" entry. It's easier to spot if you click on the "System" tab first. Both the TelescopeService and the DataDictionaryConnector should have green indicators next to them. (Click the "Refresh" button to update the GUI. Otherwise you may be looking at stale status information.) If one or both are red already, skip to the second method of re-establishing a connection described below.


Right click on the TelescopeService entry. It will pop up a menu. Select the last entry in that menu, "open GUI". This will open the Telescope GUI, which is shown below. You can also open the Telescope GUI from the command line using the command luci_telescope_gui.

LUCI Telescope GUI, when connection to IIF is bad:

Note that the status indicators at the top of the GUI all say "Unknown". That means the telescope state is unknown because the GUI cannot read data from the TCS because the connection to the IIF is bad. If the Telescope GUI does not look like this, if it shows actual telescope status (like the version shown below, including the little "..." animation in the top status lines), then the IIF connection is not bad. The GUI is being updated once per second by reading data from the TCS.

If the GUI shows "unknown" in its top line, then click on the button at the lower left corner labeled "Reconnect to IIF". This will probably work, but if the DataDictionaryConnector service is in trouble, it might not. If it works, then within a few seconds the Telescope GUI will look like below:

Telescope GUI when the IIF connection is good:

The top row of displays has a 3 dot animation "..." which changes every second when new data is read. If it looks like that, then the connection to the IIF has been restored, and you are done.

If The "Reconnect" button did not work, then you have to stop the TelescopeService and the DataDictionaryConnector.

To do this, you will need to go to the LUCI Management Console in the noVNC tab on Right click on the TelescopeService entry and select "Stop TelescopeService". Then right click on the DataDictionaryConnector and select "Stop DataDictionaryConnector". They may not stop immediately. To get an accurate view of their state, you MUST click the "Refresh" button at the bottom of the LMC GUI. They should stop within a few seconds. The color indicator to the right of the GUI entry will turn red when they stop. Keep clicking the refresh button to refresh the GUI. It does not refresh automatically.

Once they are both stopped, then the DataDictionaryConnector process must be restarted first. This is done by right clicking on the DataDictionaryConnector entry and selecting "start DataDictionaryConnector". Sometimes you will get a pop-up error message saying that the service did not restart. Ignore it and proceed. If the telescope service is accidentally restarted first, then stop it and return to a state where both processes are stopped. After you tell the DataDictionaryConnector to restart, you will have to click the refresh button again to get current status. Only after the DataDictionaryConnector has started (indicator turns green) can you restart the TelescopeService by the same right click procedure. After both the TelescopeService and the DataDictionaryConnector are restarted, then there should be a new ICE connectionn to the IIF. Opening the Telescope GUI will prove if the data is flowing.


I Attachment Action Size Date Who Comment
LMC.pngpng LMC.png manage 44 K 16 Dec 2015 - 20:08 UnknownUser LUCI LMC GUI
TELGUI.pngpng TELGUI.png manage 58 K 16 Dec 2015 - 20:55 UnknownUser Telescope GUI when the IIF connection is good:
TELGUIUnknown.pngpng TELGUIUnknown.png manage 57 K 16 Dec 2015 - 20:13 UnknownUser LUCI Telescope GUI, when connection to IIF is bad.
Topic revision: r4 - 21 Dec 2023, GlennEychaner
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