Zabbix Documentation 5.0

3.04.05.0 (current)| In development:5.2 (devel)| Unsupported:1.82.02.22.43.23.44.24.4Guidelines

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manual:config:items:item

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manual:config:items:item [2015/10/27 13:30]
martins-v linking to more info about history and trends
manual:config:items:item [2020/07/03 11:16] (current)
dimir [Unsupported items] improve link to Other parameters
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-==== - #1 Creating an item ====+==== 1 Creating an item ====
  
 === Overview === === Overview ===
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   * Click on //Create item// in the upper right corner of the screen   * Click on //Create item// in the upper right corner of the screen
   * Enter parameters of the item in the form   * Enter parameters of the item in the form
 +
 +You can also create an item by opening an existing one, pressing the //Clone// button and then saving under a different name.
  
 === Configuration === === Configuration ===
  
-{{manual:​config:​item.png|}}+The **Item** tab contains general ​item attributes.\\
  
-Item attributes:+{{manual:config:​item1.png?​600|}} 
 + 
 +All mandatory input fields are marked with a red asterisk.
  
 ^Parameter^Description^ ^Parameter^Description^
-|//​Name// ​ |This is how the item will be named.\\ The following ​macros ​can be used:\\ **$1, $2...$9** - referring to the first, second... ninth parameter of the item key\\ For example: Free disk space on $1\\ If the item key is "​vfs.fs.size[/,​free]",​ the description will automatically change to "Free disk space on /" |+|//​Name// ​ |Item name.\\ //Note// that the use of positional ​macros ​(''​$1,$2... $9'' ​- referring to the first, second... ninth parameter of the item key) is now deprecated.\\ For example: Free disk space on $1If the item key is %%"%%vfs.fs.size[/,​free]%%"%%, the description will automatically change to %%"%%Free disk space on /%%"%%  ​|
 |//​Type// ​ |Item type. See individual [[itemtypes|item type]] sections.| |//​Type// ​ |Item type. See individual [[itemtypes|item type]] sections.|
-|//​Key// ​ |Item key.\\ The supported [[itemtypes|item keys]] can be found in individual item type sections.\\ The key must be unique within a single host.\\ If key type is '​Zabbix agent',​ '​Zabbix agent (active)',​ '​Simple check' or '​Zabbix aggregate',​ the key value must be supported by Zabbix agent or Zabbix server.\\ See also: the correct [[manual:​config:​items:​item:​key|key format]]. ​ |+|//​Key// ​ |Item key (up to 2048 characters).\\ The supported [[itemtypes|item keys]] can be found in individual item type sections.\\ The key must be unique within a single host.\\ If key type is '​Zabbix agent',​ '​Zabbix agent (active)',​ '​Simple check' or '​Zabbix aggregate',​ the key value must be supported by Zabbix agent or Zabbix server.\\ See also: the correct [[manual:​config:​items:​item:​key|key format]]. ​ |
 |//Host interface// |Select the host interface. This field is available when editing an item on the host level. | |//Host interface// |Select the host interface. This field is available when editing an item on the host level. |
-|//Type of information// ​ |Type of data as stored in the database after performing conversions,​ if any.\\ **Numeric (unsigned)** - 64bit unsigned integer\\ **Numeric (float)** - floating point number\\ ​Negative values can be stored.\\ Allowed ​range (for MySQL): ​-999999999999.9999 to 999999999999.9999 (double(16,​4)).\\ Starting with Zabbix 2.2, receiving ​values in scientific notation is also supported. E.g. 1e+701e-70.\\ **Character** - character (string) ​data limited to 255 bytes\\ **Log** - log file. Must be set for log*, eventlog item keys (unless you plan to extract another type of data from these itemswith the ''​output''​ parameter).\\ **Text** - text of unlimited size| +|//Type of information// ​ |Type of data as stored in the database after performing conversions,​ if any.\\ **Numeric (unsigned)** - 64bit unsigned integer\\ **Numeric (float)** - 64bit floating point number\\ ​This type will allow precision of approximately 15 digits and range from approximately ​-1.79E+308 ​to 1.79E+308 ​(with exception of [[:​manual/​installation/​known_issues#​floating_point_values|PostgreSQL 11 and earlier versions]]).\\ Receiving ​values in scientific notation is also supported. E.g. 1.23E+71e308, 1.1E-4.\\ **Character** - short text data\\ **Log** - long text data with optional ​log related properties ​(timestampsource, severity, logeventid)\\ **Text** - long text data. See also [[#​Text_data_limits|text ​data limits]].  | 
-|//Data type// ​ |Data type is used for integer items in order to specify the expected ​data type:\\ **Boolean** - textual representation translated into either 0 or 1Thus, '​TRUE'​ is stored as 1 and '​FALSE'​ is stored as 0. All values are matched in a case-insensitive way. Currently recognized values are, for:\\ //TRUE// - true, t, yes, y, on, up, running, enabled, available\\ //FALSE// - false, f, no, n, off, down, unused, disabled, unavailable\\ Additionally,​ any non-zero numeric value is considered to be TRUE and zero is considered to be FALSE. \\ **Octal** - data in octal format\\ **Decimal** - data in decimal format\\ **Hexadecimal** - data in hexadecimal format\\ Zabbix will automatically perform the conversion to numeric.\\ The conversion is done by Zabbix server (even when a host is monitored by Zabbix proxy).  | +|//​Units// ​ |If a unit symbol is set, Zabbix will add post processing to the received value and display it with the set unit postfix.\\ By default, if the raw value exceeds 1000, it is divided by 1000 and displayed accordingly. For example, if you set //bps// and receive a value of 881764, it will be displayed as 881.76 Kbps. \\ Special processing is used for **B** (byte), **Bps** (bytes per second) units, which are divided by 1024. Thus, if units are set to **B** or **Bps** Zabbix will display:\\ 1 as 1B/1Bps\\ 1024 as 1KB/1KBps\\ 1536 as 1.5KB/​1.5KBps\\ Special processing is used if the following time-related units are used:\\ **unixtime** - translated to "​yyyy.mm.dd hh:​mm:​ss"​. To translate correctly, the received value must be a //Numeric (unsigned)//​ type of information.\\ **uptime** - translated to "​hh:​mm:​ss"​ or "N days, hh:​mm:​ss"​\\ For example, if you receive the value as 881764 (seconds), it will be displayed as "10 days, 04:​56:​04"​\\ **s** - translated to "yyy mmm ddd hhh mmm sss ms"; parameter is treated as number of seconds.\\ For example, if you receive the value as 881764 (seconds), it will be displayed as "10d 4h 56m"\\ Only 3 upper major units are shown, like "1m 15d 5h" or "2h 4m 46s". If there are no days to display, only two levels are displayed - "1m 5h" (no minutes, seconds or milliseconds are shown). Will be translated to "< 1 ms" if the value is less than 0.001.\\ ​//Note// that if a unit is prefixed with ''​!'',​ then no unit prefixes/​processing is applied to item values. ​See [[#unit_blacklisting|unit blacklisting]].  | 
-|//​Units// ​ |If a unit symbol is set, Zabbix will add post processing to the received value and display it with the set unit postfix.\\ By default, if the raw value exceeds 1000, it is divided by 1000 and displayed accordingly. For example, if you set //bps// and receive a value of 881764, it will be displayed as 881.76 Kbps. \\ Special processing is used for **B** (byte), **Bps** (bytes per second) units, which are divided by 1024. Thus, if units are set to **B** or **Bps** Zabbix will display:\\ 1 as 1B/1Bps\\ 1024 as 1KB/1KBps\\ 1536 as 1.5KB/​1.5KBps\\ Special processing is used if the following time-related units are used:\\ **unixtime** - translated to "​yyyy.mm.dd hh:​mm:​ss"​. To translate correctly, the received value must be a //Numeric (unsigned)//​ type of information.\\ **uptime** - translated to "​hh:​mm:​ss"​ or "N days, hh:​mm:​ss"​\\ For example, if you receive the value as 881764 (seconds), it will be displayed as "10 days, 04:​56:​04"​\\ **s** - translated to "yyy mmm ddd hhh mmm sss ms"; parameter is treated as number of seconds.\\ For example, if you receive the value as 881764 (seconds), it will be displayed as "10d 4h 56m"\\ Only 3 upper major units are shown, like "1m 15d 5h" or "2h 4m 46s". If there are no days to display, only two levels are displayed - "1m 5h" (no minutes, seconds or milliseconds are shown). Will be translated to "< 1 ms" if the value is less than 0.001.\\ See also the [[#unit_blacklist|unit blacklist]].  | +|//Update interval//  |Retrieve a new value for this item every N seconds. Maximum allowed update interval is 86400 seconds (1 day).\\ [[:​manual/​appendix/​suffixes|Time suffixes]] are supportede.g. 30s1m2h, 1d.\\ [[manual:​config:​macros:user_macros|User macros]] are supported.\\ A single macro has to fill the whole field. Multiple macros in a field or macros mixed with text are not supported.\\ //​Note//: ​The update interval can only be set to '​0'​ if custom intervals exist with a non-zero value. ​If set to '​0', ​and a custom interval (flexible ​or scheduled) exists with a non-zero value, the item will be polled during the custom interval duration.\\ //Note// that the first item poll after the item became active or after update interval change might occur earlier than the configured value.\\ An existing passive item can be polled for value immediately by pushing the //Check now// [[#​form_buttons|button]].  ​
-|//Use custom multiplier//  |If you enable this option, all received values will be multiplied by the integer or floating-point ​value set in the value field.\\ Use this option to convert values received in KBMBpsetc into BBpsOtherwise Zabbix cannot correctly set [[manual:​config:​triggers:suffixes|prefixes]] (K, M, G etc).\\ Starting ​with Zabbix 2.2, using scientific notation is also supported. E.g. 1e+70. ​ | +|//Custom intervals// ​ |You can create custom rules for checking the item:\\ **Flexible** - create an exception to the //Update interval// (interval with different frequency)\\ **Scheduling** - create a custom polling schedule.\\ For detailed information see [[manual:​config:​items:​item:​custom_intervals|Custom intervals]].\\ [[:​manual/​appendix/​suffixes|Time suffixes]] are supported in the //​Interval//​ field, e.g. 30s, 1m, 2h, 1d.\\ [[manual:​config:​macros:​user_macros|User macros]] are supported.\\ A single macro has to fill the whole field. Multiple macros in a field or macros mixed with text are not supported.\\ ​Scheduling is supported since Zabbix ​3.0.0.\\ //Note//: Not available for Zabbix agent active items. ​ | 
-|//Update interval (in sec)// ​ |Refresh this item every N seconds.\\ //Note//: If set to '​0', ​the item will not be polled. However, if a custom interval (flexible/schedulingalso exists with a non-zero value, the item will be polled during the custom interval duration.| +|//History storage period// ​ |Select either:\\ **Do not keep history** - item history is not stored. Useful for master items if only dependent items need to keep history.\\ This setting cannot be overridden by global housekeeper [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|settings]].\\ **Storage period** - specify the duration of keeping ​detailed history in the database ​(1 hour to 25 years). Older data will be removed by the housekeeper. Stored in seconds.\\ [[:​manual/​appendix/​suffixes|Time suffixes]] are supported, e.g. 2h1d. [[manual:​config:​macros:​user_macros|User macros]] are supported.\\ The //Storage period// ​value can be overridden globally in //​Administration -> General -> [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|Housekeeper]]//​.\\ If global ​overriding ​setting exists, a green {{manual:​config:​info.png|}} ​info icon is displayed. If you position your mouse on it, a warning message is displayed, e. g. //​Overridden by global housekeeper settings (1d)//.\\ It is recommended to keep the recorded values for the smallest possible ​time to reduce the size of value history in the database. Instead of keeping ​long history of values, you can keep longer data of trends.\\ See also [[:​manual/​config/​items/​history_and_trends|History and trends]]. ​ | 
-|//Custom intervals// ​ |You can create custom rules for checking the item:\\ **Flexible** - create an exception to the //Update interval// (interval with different frequency)\\ **Scheduling** - create a custom polling schedule.\\ For detailed information see [[manual:​config:​items:​item:​custom_intervals|Custom intervals]]. Scheduling is supported since Zabix 3.0.0.\\ //Note//: Not available for Zabbix agent active items. ​ | +|//Trend storage period// ​ |Select either:\\ **Do not keep trends** - trends are not stored.\\ This setting cannot be overridden by global housekeeper [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|settings]].\\ **Storage period** - specify the duration of keeping ​aggregated (hourly min, max, avg, count) history in the database ​(1 day to 25 years). Older data will be removed by the housekeeper. Stored in seconds.\\ [[:​manual/​appendix/​suffixes|Time suffixes]] are supported, e.g. 24h1d. [[manual:​config:​macros:​user_macros|User macros]] are supported.\\ The //Storage period// ​value can be overridden globally in //​Administration -> General -> [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|Housekeeper]]//​.\\ If global ​overriding ​setting exists, a green {{manual:​config:​info.png|}} ​info icon is displayed. If you position your mouse on it, a warning message is displayed, e. g. //​Overridden by global housekeeper settings (7d)//.\\ //Note:// Keeping trends is not available for non-numeric data - character, log and text.\\ See also [[:​manual/​config/​items/​history_and_trends|History and trends]]. ​ | 
-|//History storage period\\ (in days)//  |Number of days to keep detailed history in the database. Older data will be removed by the housekeeper.\\ ​Starting with Zabbix 2.2this value can be overridden globally in //​Administration -> General -> [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|Housekeeper]]//​. If the global setting exists, a warning message is displayed:​\\ ​{{manual:​config:​override_item.png|}}\\ It is recommended to keep the recorded values for the smallest possible ​number of days to reduce the size of value history in the database. Instead of keeping long history of values, you can keep longer data of trends.\\ See also [[:​manual/​config/​items/​history_and_trends|History and trends]]. ​ | +|//Show value// ​ |Apply value mapping to this item. Value mapping does not change received values, it is for displaying data only.\\ It works with //​Numeric(unsigned)//,​ //​Numeric(float)//​ and //​Character// ​items.\\ For example, "​Windows service states"​.| 
-|//Trend storage period\\ (in days)//  |Keep aggregated (hourly min, max, avg, count) ​detailed ​history ​for N days in the database. Older data will be removed by the housekeeper.\\ ​Starting with Zabbix 2.2this value can be overridden globally in //​Administration -> General -> [[manual:​web_interface:​frontend_sections:​administration:​general#​housekeeper|Housekeeper]]//​. If the global setting exists, a warning message is displayed:​\\ ​{{manual:​config:​override_trends.png|}}\\ //Note:// Keeping trends is not available for non-numeric data - character, log and text.\\ See also [[:​manual/​config/​items/​history_and_trends|History and trends]].  ​+|//Log time format// ​ |Available for items of type **Log** only. Supported placeholders:​\\ ​    * **y**: //Year (1970-2038)//\\     * **M**: //Month (01-12)//​\\ ​    * **d**: //Day (01-31)//​\\ ​    * **h**: //Hour (00-23)//​\\ ​    * **m**: //Minute (00-59)//​\\ ​    * **s**: //Second (00-59)//​\\ ​    If left blank the timestamp will not be parsed.\\ For example, consider the following line from the Zabbix agent log file:\\ " 23480:​20100328:​154718.045 Zabbix agent started. Zabbix 1.8.2 (revision 11211)."​\\ It begins with six character positions for PID, followed by date, time, and the rest of the line.\\ Log time format for this line would be "​pppppp:​yyyyMMdd:​hhmmss"​.\\ Note that "​p"​ and ":"​ chars are just placeholders and can be anything but "​yMdhms"​. |
-|//Store value// ​ |**As is**  - no pre-processing\\ **Delta (speed per second)** - evaluate value as (**value**-**prev_value**)/​(**time**-**prev_time**),​ where\\ //value// - current value\\ //​value_prev//​ - previously received value\\ //time// - current timestamp\\ //​prev_time//​ - timestamp of previous value\\ This setting is extremely useful to get speed per second for a constantly growing value.\\ //Note//: If current value is smaller than the previous value, Zabbix discards that difference (stores nothing) and waits for another value. This helps to work correctly with, for instance, a wrapping (overflow) of 32-bit SNMP counters.\\ **Delta (simple change)** - evaluate as (**value**-**prev_value**),​ where\\ //value// - current value\\ //​value_prev//​ - previously received value+
-|//Show value// ​ |Apply value mapping to this item. Value mapping does not change received values, it is for displaying data only.\\ It works with integer ​items only.\\ For example, "​Windows service states"​.| +
-|//Log time format// ​ |Available for items of type **Log** only. Supported placeholders:​\\ ​    * **y**: //Year (0001-9999)//\\     * **M**: //Month (01-12)//​\\ ​    * **d**: //Day (01-31)//​\\ ​    * **h**: //Hour (00-23)//​\\ ​    * **m**: //Minute (00-59)//​\\ ​    * **s**: //Second (00-59)//​\\ ​    If left blank the timestamp will not be parsed.\\ For example, consider the following line from the Zabbix agent log file:\\ " 23480:​20100328:​154718.045 Zabbix agent started. Zabbix 1.8.2 (revision 11211)."​\\ It begins with six character positions for PID, followed by date, time, and the rest of the line.\\ Log time format for this line would be "​pppppp:​yyyyMMdd:​hhmmss"​.\\ Note that "​p"​ and ":"​ chars are just placeholders and can be anything but "​yMdhms"​. |+
 |//New application// ​ |Enter the name of a new application for the item.  | |//New application// ​ |Enter the name of a new application for the item.  |
 |//​Applications// ​ |Link item to one or more existing applications. ​ | |//​Applications// ​ |Link item to one or more existing applications. ​ |
-|//​Populates host inventory field// ​ |You can select a host inventory field that the value of item will populate. This will work if automatic [[manual:​config:​hosts:​inventory|inventory]] population is enabled for the host.  |+|//​Populates host inventory field// ​ |You can select a host inventory field that the value of item will populate. This will work if automatic [[manual:​config:​hosts:​inventory|inventory]] population is enabled for the host.\\ This field is not available if //Type of information//​ is set to '​Log'​.  |
 |//​Description// ​ |Enter an item description. ​ | |//​Description// ​ |Enter an item description. ​ |
 |//​Enabled// ​ |Mark the checkbox to enable the item so it will be processed. ​  | |//​Enabled// ​ |Mark the checkbox to enable the item so it will be processed. ​  |
  
-You can also create an item by opening an existing one, pressing the //Clone// button and then saving under a different name. +<​note>​Item type specific fields are described on [[itemtypes|corresponding pages]].<​/note>
 <​note>​When editing an existing [[manual:​config:​templates|template]] level item on a host level, a number of fields are read-only. You can use the link in the form header and go to the template level and edit them there, keeping in mind that the changes on a template level will change the item for all hosts that the template is linked to.</​note>​ <​note>​When editing an existing [[manual:​config:​templates|template]] level item on a host level, a number of fields are read-only. You can use the link in the form header and go to the template level and edit them there, keeping in mind that the changes on a template level will change the item for all hosts that the template is linked to.</​note>​
  
-== Unit blacklist ==+== Item value preprocessing == 
 + 
 +The **Preprocessing** tab allows to define [[:​manual/​config/​items/​preprocessing|transformation rules]] for the received values. 
 + 
 +=== Testing === 
 + 
 +It is possible to test an item and, if configured correctly, get a real value in return. Testing can occur even before an item is saved. 
 + 
 +Testing is available for host and template items, item prototypes and low-level discovery rules. Testing is not available for active items. 
 + 
 +Item testing is available for the following passive item types: 
 + 
 +  * Zabbix agent 
 +  * SNMP agent (v1, v2, v3) 
 +  * IPMI agent 
 +  * SSH checks 
 +  * Telnet checks 
 +  * JMX agent 
 +  * Simple checks (except ''​icmpping*'',​ ''​vmware.*''​ items) 
 +  * Zabbix internal 
 +  * Zabbix aggregate 
 +  * Calculated items 
 +  * External checks 
 +  * Database monitor 
 +  * HTTP agent 
 + 
 +To test an item, click on the //Test// button at the bottom of the item configuration form. Note that the //Test// button will be disabled for items that cannot be tested (like active checks, excluded simple checks). 
 + 
 +{{:​manual:​config:​items:​item_test_button.png|}} 
 + 
 +The item testing form has fields for the required host parameters (host address, port, proxy name/no proxy). These fields are context aware: 
 + 
 +  * The values are pre-filled when possible, i.e. for items requiring an agent, by taking the information from the selected agent interface of the host 
 +  * The values have to be filled manually for template items 
 +  * The fields are disabled when not needed in the context of the item type (e.g. the host address field is disabled for calculated and aggregate items, the proxy field is disabled for calculated items) 
 + 
 +To test the item, click on //Get value//. If the value is retrieved successfully,​ it will fill the //Value// field, moving the current value (if any) to the //Previous value// field while also calculating the //Prev. time// field, i.e. the time difference between the two values (clicks) and trying to detect an EOL sequence and switch to CRLF if detecting %%"​%%\n\r%%"​%% in retrieved value. 
 + 
 +{{:​manual:​config:​items:​item_test.png?​600|}} 
 + 
 +If the configuration is incorrect, an error message is displayed describing the possible cause. 
 + 
 +{{:​manual:​config:​items:​item_test_error.png|}} 
 + 
 +A successfully retrieved value from host can also be used to test [[:​manual/​config/​items/​preprocessing#​testing|preprocessing steps]].  
 +=== Form buttons === 
 + 
 +Buttons at the bottom of the form allow to perform several operations. 
 + 
 +|{{manual:​config:​button_add.png|}} ​ |Add an item. This button is only available for new items. ​ | 
 +|{{manual:​config:​button_update.png|}} ​ |Update the properties of an item.  | 
 +|{{manual:​config:​button_clone.png|}} ​ |Create another item based on the properties of the current item.  | 
 +|{{manual:​config:​button_execute.png|}} ​ |Execute a check for a new item value immediately. Supported for **passive** checks only (see [[:​manual/​config/​items/​check_now|more details]]).\\ //Note// that when checking for a value immediately,​ configuration cache is not updated, thus the value will not reflect very recent changes to item configuration. ​ | 
 +|{{manual:​config:​button_test.png|}} ​ |Test if item configuration is correct by getting a value. ​ | 
 +|{{manual:​config:​button_clear.png|}} ​ |Delete the item history and trends. ​ | 
 +|{{manual:​config:​button_delete.png|}} ​ |Delete the item.  | 
 +|{{manual:​config:​button_cancel.png|}} ​ |Cancel the editing of item properties. ​ | 
 + 
 +=== Text data limits === 
 + 
 +Text data limits depend on the database backend. Before storing text values in the database they get truncated to match the database value type limit: 
 + 
 +^ Database ^  Type of information ​ ^^^ 
 +^ ::: ^ Character ​  ^ Log              ^ Text             ^ 
 +| MySQL      | 255 characters | 65536 bytes      | 65536 bytes      | 
 +| PostgreSQL | 255 characters | 65536 characters | 65536 characters | 
 +| Oracle ​    | 255 characters | 65536 characters | 65536 characters | 
 + 
 +=== Unit blacklisting === 
 + 
 +By default, specifying a unit for an item results in a multiplier prefix being added - for example, an incoming value '​2048'​ with unit '​B'​ would be displayed as '​2KB'​.  
 + 
 +Any unit, however, can be prevented from being converted by using a ''​!''​ prefix, for example ''​!B''​. To better illustrate how the conversion works with and without the blacklisting,​ see the following examples of values and units: 
 + 
 +  1024 !B -> 1024 B 
 +  1024 B -> 1 KB 
 +  61 !s -> 61 s 
 +  61 s -> 1m 1s 
 +  0 !uptime -> 0 uptime 
 +  0 uptime -> 00:00:00 
 +  0 !! -> 0 ! 
 +  0 ! -> 0 
 + 
 +<​note>​Before Zabbix 4.0, there was a hardcoded unit blacklist ​consisting of ''​ms'',​ ''​rpm'',​ ''​RPM'',​ ''​%''​. This blacklist has been deprecated, thus the correct way of blacklisting such units is ''​!ms'',​ ''​!rpm'',​ ''​!RPM'',​ ''​!%''​.</​note>​ 
 + 
 +=== Custom script limit ===
  
-By default, specifying a unit for an item will result in a multiplier prefix being added - for example, value 2048 with unit B would be displayed as 2KB. For a pre-defined,​ hardcoded list of units this is prevented:+Available custom script length depends on the database used:
  
-  ​ms +|//​Database//​ |//Limit in characters //| //Limit in bytes //| 
-  RPM +|**MySQL**|65535|65535| 
-  rpm +|**Oracle Database**|2048|4000| 
-  %+|**PostgreSQL**|65535|not limited| 
 +|**SQLite (only Zabbix proxy)**|65535|not limited|
  
-Note that both lowercase and uppercase **rpm** (//rpm// and //RPM//) strings are blacklisted. 
 === Unsupported items === === Unsupported items ===
  
-An item can become unsupported if its value cannot be retrieved for some reason. Such items are still rechecked at a fixed interval, configurable in [[manual:​web_interface:​frontend_sections:​administration:​general?&#​other_parameters|Administration section]].+An item can become unsupported if its value cannot be retrieved for some reason. Such items are still rechecked at a fixed interval, configurable in 
 +//​Administration -> General -> [[manual:​web_interface:​frontend_sections:​administration:​general#​other_parameters|Other parameters]]//.
  
 +Unsupported items are reported as having a NOT SUPPORTED state.