To see all of the alarms you need to use the -a option.
If the -a (all) option is specified, show alarms do not perform any masking and displays all CRITICAL, MAJOR, MINOR, MAINTENANCE, SUPPRESSED, and INITIAL alarms../show alarms -a
To see the differences in the output with and without the -a option.
[
[email protected] vnmsh]$ ./show alarms | wc -l
15861
[
[email protected] vnmsh]$ ./show alarms -a | wc -l
20520