Hello AlexBCT.
Counter, Gauge and String are just measure types, not a format types.
String is a text, and the difference between counter and gauge is bit sutil (similar to counter and gauge difference in SNMP).
F5-BIGIP-LOCAL-MIB::ltmServerSslMaxActiveHandshake."/Common/crypto-client-default-serverssl" = Gauge32: 0
F5-BIGIP-LOCAL-MIB::ltmServerSslStatHandshakeFailures."/Common/serverssl" = Counter64: 0
Counters only increase, but gauge could increase or decrease (it allows you to set a negative increment).
[root@spissa:Active:Standalone] alertd # istats -help
Usage: istats <operation> [-s <segment-filename>] <key> [<value>]
<operation> is one of: 'set' 'incr' 'get' 'remove' 'dump' 'drop_row'
'drop_column' 'clear_row'
<key> is a single quoted argument: "keyspace <table> <column> <value> ... <type> <measure>"
(like "ltm.pool /Common/mypool counter mystat")
<type> is one of: 'counter' 'gauge' 'string' 'text' 'signed' 'unsigned' 'bin'
'dec' 'hex' 'timestamp' 'timeval' 'uinthex'
<value> must be specified for 'set' and 'incr', and must be an integer for 'incr'
The <value> for a gauge may be negative. Use 2 dashes before the
negative value (like 'incr "... gauge ..." -- -1')
Regards,
Dario.