use MongoDB;
use Data::Dumper;

my $mdb = MongoDB->connect( 'mongodb://xxxxxxx', {
  username => 'xxxxx@xxxxxx.COM',
  auth_mechanism => 'GSSAPI',
});

my $db = $mdb->get_database('testdb');

my $cfg = $db->get_collection('test_coll');

my $result = $cfg->insert_one({
  name => 'test_name',
  test_field => 'this_is_a_test',
});

my $id = $result->inserted_id();
print "Inserted: $id\n";

my $all_cfg = $cfg->find;

while ( my $c = $all_cfg->next ) {
  print Dumper $c;
}

##</code><code>##

MongoDB::AuthError: Authentication to //xxxxxxx:27017 failed: MongoDB::AuthError: GSSAPI error: MongoDB::AuthError: Could not start GSSAPI. Did you run kinit?  Error was: no mechanism available; SASL(-4): no mechanism available: No worthy mechs found; client_start error. (Callbacks?)