Both getDynamicPortRange() and sanitizePortRange() could produce
and error, and the error message was currently discarded, silently
falling back to using the default port range.
This patch:
- Moves the fallback message from getDynamicPortRange() to getDefaultPortRange(),
which is where the actual fallback occurs.
- Logs the fallback message and the error that causes the fallback.
The message/error is currently printed at the INFO level, but could be raised
to a WARN, depending on what kind of situations can cause the error.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>