Hi Enrico,

issuing a third-party gfal-copy using srm+gsiftp -> srm+https a strange error occurs and the transfer fails, for example:

gfal-copy -vvv srm://storm-test.cr.cnaf.infn.it:8444/folder/test-andre srm://storm-test.cr.cnaf.infn.it:8444/disk/test-andre
[...]
WARNING  Transfer failed with: [srm_do_transfer][gfalt_copy_file][perform_copy][perform_local_copy][streamed_copy][gfal_plugin_writeG][davix2gliberr] Impossible to write, no buffer. (file was opened only for reading?)

After a deep investigation we have figured out that the problem is probably related to the creation of an https TURL triggered by an srm request. In fact, with a TURL like this one, gfal tries to perform the transfer issuing a POST command which is not admitted by WebDAV. This is also the reason of a 405 error (method not allowed) found in the logs.

On the other hand, trying to perform the same transfer only using the davs protocol for the destination, namely
gfal-copy -vvv srm://storm-test.cr.cnaf.infn.it:8444/folder/test-andre davs://transfer-test.cr.cnaf.infn.it:8443/disk/test-andre
gfal issues a PUT command and the transfer succeeds.

For this reason, we think that adding the davs protocol to the admitted protocols of the StoRM backend for TURLs creation, it could solve the issue.

Please, correct me if I am wrong or I made any mistake.
Thank you very much for your help!

Andrea