There is a bug in NXLog Community Edition 2.10.2150, with module
im_ssl regarding opening CA files.
NXLog seems to create a file descriptor for the CA file each time a new connection is made. That is, NXLog opens the file again and again. If NXLog runs on Linux, this can quickly hit the OS limit of maximum number of files open.
The following error is seen repeatedly once the OS limit of file descriptors is reached: