check_mssql_health 220.127.116.11 without definitions in freetds.conf works like a charm for default database. Trying the same with a named instance means using a different port than 1433 is not working and I’m not sure if this is a bug of check_mssql_health or a subsequent error due to a bug of freetds. Based on Ubuntu 16.04 LTS the provided freetds package version is 0.91-6.1build1 and I can’t identify whether this bug fix is included in this version.
This freetds bug causes check_mssql_health to fail with --hostname (see also #10 and #22). Therefore, I’m always using --server instead and this works for default instance resp. default port, but not for a named instance with a different port (means check_mssql_health still trys to connect to 1433).
@lausser: Does this belong to check_mssql_health and can be fixed? Or do I have to update freetds?