13 What's new in Zabbix 2.2.8

History related macros - {ITEM.VALUE}, {ITEM.LASTVALUE} and the {host:key.last()} functional macro - now obey the ZBX_HISTORY_PERIOD constant. This limits the amount of data the macro has to sift through and results in better performance.

History cache has been optimized to better handle a situation when it's being flooded with hundreds of thousands of values from less than a thousand items.
SNMP polling logic has been improved to always retry at least once. This should make Zabbix more resilient to network errors.
SNMP values of type OID are now supported.
SNMP validation error messages from Zabbix 2.2.7 have been improved by including the sent and received OIDs:

SNMP response from host "gateway" contains variable bindings that do not match the request: sent ".1.3.6.1.2.1.2.2.1.16.9", received ".1.3.6.1.2.1.2.2.1.16.9.0"For bulk requests, these are logged at DebugLevel=3. For single-variable requests, these are logged at DebugLevel=4.
If an IPMI device reports a threshold sensor and a discrete sensor under the same name, the threshold sensor is now preferred. This might fix strange readings (like "1" for fan RPM) or "not supported" errors.
Message logging on IBM DB2 errors has been improved. Now additional information is printed to the log file - database name on connection errors and SQL query on failed queries.

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