The following is a list of known issues that may be seen when installing CIAO. If you encounter a problem that is not listed here, contact CXC Helpdesk for assistance.
error while loading shared libraries: libxml2.so.2: cannot open shared object file: No such file or directory
The DS9 smoke test will run for a long time (of order 10 minutes) and then fail on Ubuntu 25.10 systems due to an incompatibility with the version of libxml2 (version 2.14.0).
For a work around please follow the instructions on the platform support page.
A sample diff log from test ds9-smoke001:
13c13 < 1.73363528e+02 2.58432381e+01 --- > 1.73363528e+02 2.58432382e+01 22c22 < 1.73357457e+02 2.58464050e+01 --- > 1.73357457e+02 2.58464051e+01 75c75 < 1.73322543e+02 2.58736917e+01 --- > 1.73322543e+02 2.58736916e+01 99c99 < 1.73310395e+02 2.58821467e+01 --- > 1.73310395e+02 2.58821466e+01
Often rerunning the test will resolve the difference. (Frequently it is due to a timing issue between certain XPA commands.)
The smoke tests use commands from the Apple Xcode package. If you see warnings like
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
then you need to update your version of Xcode.
Several CIAO applications make use of resource files in the users home directory. These typically contain global application preferences. The list of resource files, or .rc files, is shown below.
If users have made customizations to these file it may cause the CIAO smoke tests to fail. This has been seen several times with sherpa users who have setup to use pyfits (rather than crates) and are upgrading to the lastest version of CIAO.
Users should move their customized version of these files to another directory and re-try the smoke tests. The files will get re-created and the customizations can be re-introduced in the new version of these files.
Users who have made customizations to their $HOME/.ipython-ciao setup files will need to check their customizations after CIAO is installed.
The Sherpa smoke test fails and the log contains these errors:
ERROR: test_image (sherpa.image.tests.test_image.test_image) ---------------------------------------------------------------------- Traceback (most recent call last): ValueError: total size of new array must be unchanged
This is an intermittent error in the code that Sherpa uses to talk with DS9 via XPA. Run the smoke tests a second time and the errors should go away. If they do not, contact CXC Helpdesk for further assistance.