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os_mon(7) [linux man page]

os_mon(7)						   Erlang Application Definition						 os_mon(7)

NAME
os_mon - OS Monitoring Application DESCRIPTION
The operating system monitor, OS_Mon, provides the following services: * cpu_sup CPU load and utilization supervision (Unix) * disksup Disk supervision(Unix, Windows) * memsup Memory supervision (Unix, Windows, VxWorks) * os_sup Interface to OS system messages (Solaris, Windows) To simplify usage of OS_Mon on distributed Erlang systems, it is not considered an error trying to use a service at a node where it is not available (either because OS_Mon is not running, or because the service is not available for that OS, or because the service is not started). Instead, a warning message is issued via error_logger and a dummy value is returned, which one is specified in the man pages for the respective services. CONFIGURATION
When OS_Mon is started, by default all services available for the OS, except os_sup , are automatically started. This configuration can be changed using the following application configuration parameters: start_cpu_sup = bool() : Specifies if cpu_sup should be started. Defaults to true . start_disksup = bool() : Specifies if disksup should be started. Defaults to true . start_memsup = bool() : Specifies if memsup should be started. Defaults to true . start_os_sup = bool() : Specifies if os_sup should be started. Defaults to false . Configuration parameters effecting the different OS_Mon services are described in the respective man pages. See config(5) for information about how to change the value of configuration parameters. SNMP MIBS
The following MIBs are defined in OS_Mon: OTP-OS-MON-MIB : This MIB contains objects for instrumentation of disk, memory and CPU usage of the nodes in the system. The MIB is stored in the mibs directory. It is defined in SNMPv2 SMI syntax. An SNMPv1 version of the MIB is delivered in the mibs/v1 directory. The compiled MIB is located under priv/mibs , and the generated .hrl file under the include directory. To compile a MIB that IMPORTS the OTP-OS-MON-MIB , give the option {il, ["os_mon/priv/mibs"]} to the MIB compiler. If the MIB should be used in a system, it should be loaded into an agent with a call to os_mon_mib:load(Agent) , where Agent is the pid or registered name of an SNMP agent. Use os_mon_mib:unload(Agent) to unload the MIB. The implementation of this MIB uses Mnesia to store a cache with data needed, which implicates that Mnesia must be up and running. The MIB also use functions defined for the OTP-MIB , thus that MIB must be loaded as well. SEE ALSO
cpu_sup(3erl) , disksup(3erl) , memsup(3erl) , os_sup(3erl) , nteventlog(3erl) , snmp(3erl) . Ericsson AB os_mon 2.2.5 os_mon(7)

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disksup(3erl)						     Erlang Module Definition						     disksup(3erl)

NAME
disksup - A Disk Supervisor Process DESCRIPTION
disksup is a process which supervises the available disk space in the system. It is part of the OS_Mon application, see os_mon(7) . Avail- able for Unix and Windows. Periodically checks the disks. For each disk or partition which uses more than a certain amount of the available space, the alarm {{disk_almost_full, MountedOn}, []} is set. On Unix : All (locally) mounted disks are checked, including the swap disk if it is present. On WIN32 : All logical drives of type "FIXED_DISK" are checked. Alarms are reported to the SASL alarm handler, see alarm_handler(3erl) . To set an alarm, alarm_handler:set_alarm(Alarm) is called where Alarm is the alarm specified above. The alarms are cleared automatically when the alarm cause is no longer valid. CONFIGURATION
The following configuration parameters can be used to change the default values for time interval and threshold: disk_space_check_interval = int()>0 : The time interval, in minutes, for the periodic disk space check. The default is 30 minutes. disk_almost_full_threshold = float() : The threshold, as percentage of total disk space, for how much disk can be utilized before the disk_almost_full alarm is set. The default is 0.80 (80%). See config(5) for information about how to change the value of configuration parameters. EXPORTS
get_disk_data() -> [DiskData] Types DiskData = {Id, KByte, Capacity} Id = string() KByte = int() Capacity = int() Returns the result of the latest disk check. Id is a string that identifies the disk or partition. KByte is the total size of the disk or partition in kbytes. Capacity is the percentage of disk space used. The function is asynchronous in the sense that it does not invoke a disk check, but returns the latest available value. Returns [{"none",0,0}] if disksup is not available. get_check_interval() -> MS Types MS = int() Returns the time interval, in milliseconds, for the periodic disk space check. set_check_interval(Minutes) -> ok Types Minutes = int()>=1 Changes the time interval, given in minutes, for the periodic disk space check. The change will take effect after the next disk space check and is non-persist. That is, in case of a process restart, this value is forgotten and the default value will be used. See Configuration above. get_almost_full_threshold() -> Percent Types Percent = int() Returns the threshold, in percent, for disk space utilization. set_almost_full_threshold(Float) -> ok Types Float = float(), 0=<Float=<1 Changes the threshold, given as a float, for disk space utilization. The change will take effect during the next disk space check and is non-persist. That is, in case of a process restart, this value is forgotten and the default value will be used. See Configuration above. SEE ALSO
alarm_handler(3erl) , os_mon(3erl) Ericsson AB os_mon 2.2.5 disksup(3erl)

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