snmp(3)

MODULE
snmp - Interface functions to the SNMP toolkit

DESCRIPTION

The module snmp contains interface functions to the SNMP toolkit.

Common Data Types

The following datatypes are used in the functions below:

    *   oid() = [byte()]

The oid() type is used to represent an ASN.1 OBJECT IDENTIFIER.

EXPORTS

config() -> ok | {error, Reason}

    A simple interactive SNMP agent configuration tool. Simple configuration files can be generated, but more complex configurations still have to be edited manually.

    The tool is a textual based tool that asks some questions and generates sys.config and *.conf files.

    Note that if the application shall support version 3, then the crypto app must be started before running this function (password generation).

start() -> ok | {error, Reason}
start(Type) -> ok | {error, Reason}

    Types
        Type = start_type()

    Starts the SNMP application.

    See application for more info.

start_agent() -> ok | {error, Reason}
start_agent(Type) -> ok | {error, Reason}

    Types
        Type = start_type()

    The SNMP application consists of several entities, of which the agent is one. This function starts the agent entity of the application.

    Note that the only way to actually start the agent in this way is to add the agent related config after starting the application (e.g it cannot be part of the normal application config; sys.config). This is done by calling: application:set_env(snmp, agent, Conf).

    The default value for Type is normal.

start_manager() -> ok | {error, Reason}
start_manager(Type) -> ok | {error, Reason}

    Types
        Type = start_type()

    The SNMP application consists of several entities, of which the manager is one. This function starts the manager entity of the application.

    Note that the only way to actually start the manager in this way is to add the manager related config after starting the application (e.g it cannot be part of the normal application config; sys.config). This is done by calling: application:set_env(snmp, manager, Conf).

    The default value for Type is normal.

versions1() -> {ok, Info} | {error, Reason}
versions2() -> {ok, Info} | {error, Reason}

    Types
        Info = [info()]
        info() = term()
        Reason = term()

    Utility functions used to retreive some system and application info.

    The difference between the two functions is in how they get the modules to check. versions1 uses the app-file and versions2 uses the function application:get_key.

print_version_info() -> void()
print_version_info(Prefix) -> void()

    Types
        Prefix = string() | integer()

    Utility function(s) to produce a formated printout of the versions info generated by the versions1 function

    This is the same as doing, e.g.:
               {ok, V} = snmp:versions1(),
               snmp:print_versions(V).

print_versions(VersionInfo) -> void()
print_versions(Prefix, VersionInfo) -> void()

    Types
        VersionInfo = [version_info()]
        version_info() = term()
        Prefix = string() | integer()

    Utility function to produce a formated printout of the versions info generated by the versions1 and versions2 functions

    Example:
               {ok, V} = snmp:versions1(),
               snmp:print_versions(V).

date_and_time() -> DateAndTime

    Types
        DateAndTime = [int()]

    Returns current date and time as the data type DateAndTime, as specified in RFC1903. This is an OCTET STRING.

date_and_time_to_universal_time_dst(DateAndTime) -> [utc()]

    Types
        DateAndTime = [int()]
        utc() = {{Y, Mo, D}, {H, M, S}}

    Converts a DateAndTime list to a list of possible universal time(s). The unversal time value on the same format as defined in calendar(3).

date_and_time_to_string(DateAndTime) -> string()

    Types
        DateAndTime = [int()]

    Converts a DateAndTime list to a printable string, according to the DISPLAY-HINT definition in RFC1903.

local_time_to_date_and_time_dst(Local) -> [DateAndTime]

    Types
        Local = {{Y, Mo, D}, {H, M, S}}
        DateAndTime = [int()]

    Converts a local time value to a list of possible DateAndTime list(s). The local time value on the same format as defined in calendar(3).

universal_time_to_date_and_time(UTC) -> DateAndTime

    Types
        UTC = {{Y, Mo, D}, {H, M, S}}
        DateAndTime = [int()]

    Converts a universal time value to a DateAndTime list. The unversal time value on the same format as defined in calendar(3).

validate_date_and_time(DateAndTime) -> bool()

    Types
        DateAndTime = term()

    Checks if DateAndTime is a correct DateAndTime value, as specified in RFC1903. This function can be used in instrumentation functions to validate a DateAndTime value.

log_to_txt(LogDir, Mibs, OutFile, LogName, LogFile) -> ok | {error, Reason}
log_to_txt(LogDir, Mibs, OutFile, LogName, LogFile, Start) -> ok | {error, Reason}
log_to_txt(LogDir, Mibs, OutFile, LogName, LogFile, Start, Stop) -> ok | {error, Reason}

    Types
        LogDir = string()
        Mibs = [MibName]
        OutFile = string()
        MibName = string()
        LogName = string()
        LogFile = string()
        Start = Stop = null | datetime() | {local_time, datetime()} | {universal_time, datetime()}
        Reason = term()

    Converts an Audit Trail Log to a readable text file, where each item has a trailing TAB character, and any TAB character in the body of an item has been replaced by ESC TAB.

    The function can be used on a running system, or by copying the entire log directory and calling this function. SNMP must be running in order to provide MIB information.

    LogDir is the name of the directory where the audit trail log is stored. Mibs is a list of Mibs to be used. The function uses the information in the Mibs to convert for example object identifiers to their symbolic name. OutFile is the name of the generated textfile. LogName is the name of the log, LogFile is the name of the log file. Start is the start (first) date and time from which log events will be converted and Stop is the stop (last) date and time to which log events will be converted.

    The format of an audit trail log text item is as follows:

    Tag Addr - Community [TimeStamp] Vsn
    PDU

    where Tag is request, response, report, trap or inform; Addr is IP:Port (or comma space separated list of such); Community is the community parameter (SNMP version v1 and v2), or SecLevel:"AuthEngineID":"UserName" (SNMP v3); TimeStamp is a date and time stamp, and Vsn is the SNMP version. PDU is a textual version of the protocol data unit. There is a new line between Vsn and PDU.

change_log_size(LogName, NewSize) -> ok | {error, Reason}

    Types
        LogName = string()
        NewSize = {MaxBytes, MaxFiles}
        MaxBytes = integer()
        MaxFiles = integer()
        Reason = term()

    Changes the log size of the Audit Trail Log. The application must be configured to use the audit trail log function. Please refer to disk_log(3) in Kernel Reference Manual for a description of how to change the log size.

    The change is permanent, as long as the log is not deleted. That means, the log size is remebered across reboots.

See Also

calendar(3)

AUTHORS
Martin Björklund - support@erlang.ericsson.se
Klas Eriksson - support@erlang.ericsson.se