{
    "mode": "man",
    "parameter": "rrdupdate",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/rrdupdate/1/json",
    "generated": "2026-06-03T01:48:39Z",
    "synopsis": "rrdtool {update | updatev} filename [--template|-t ds-name[:ds-name]...]\n[--skip-past-updates|-s] [--daemon|-d address] [--] N:value[:value]...\ntimestamp:value[:value]...  at-timestamp@value[:value]...",
    "sections": {
        "NAME": {
            "content": "rrdupdate - Store a new set of values into the RRD\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "rrdtool {update | updatev} filename [--template|-t ds-name[:ds-name]...]\n[--skip-past-updates|-s] [--daemon|-d address] [--] N:value[:value]...\ntimestamp:value[:value]...  at-timestamp@value[:value]...\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "The update function feeds new data values into an RRD. The data is time aligned\n(interpolated) according to the properties of the RRD to which the data is written.\n\nupdatev This alternate version of update takes the same arguments and performs the same\nfunction. The v stands for verbose, which describes the output returned. updatev\nreturns a list of any and all consolidated data points (CDPs) written to disk as a\nresult of the invocation of update. The values are indexed by timestamp (timet), RRA\n(consolidation function and PDPs per CDP), and data source (name).  Note that\ndepending on the arguments of the current and previous call to update, the list may\nhave no entries or a large number of entries.\n\nSince updatev requires direct disk access, the --daemon option cannot be used with\nthis command.\n\nfilename\nThe name of the RRD you want to update.\n\n--template|-t ds-name[:ds-name]...\nBy default, the update function expects its data input in the order the data sources\nare defined in the RRD, excluding any COMPUTE data sources (i.e. if the third data\nsource DST is COMPUTE, the third input value will be mapped to the fourth data source\nin the RRD and so on). This is not very error resistant, as you might be sending the\nwrong data into an RRD.\n\nThe template switch allows you to specify which data sources you are going to update\nand in which order. If the data sources specified in the template are not available\nin the RRD file, the update process will abort with an error message.\n\nWhile it appears possible with the template switch to update data sources\nasynchronously, RRDtool implicitly assigns non-COMPUTE data sources missing from the\ntemplate the *UNKNOWN* value.\n\nDo not specify a value for a COMPUTE DST in the update function. If this is done\naccidentally (and this can only be done using the template switch), RRDtool will\nignore the value specified for the COMPUTE DST.\n\nThe caching daemon rrdcached cannot be used together with templates yet.\n\n--skip-past-updates|-s\nWhen updating an rrd file with data earlier than the latest update already applied,\nrrdtool will issue an error message and abort. This option instructs rrdtool to\nsilently skip such data. It can be useful when re-playing old data into an rrd file\nand you are not sure how many updates have already been applied.\n\n--daemon|-d address\nIf given, RRDtool will try to connect to the caching daemon rrdcached at address. If\nthe connection is successfully established the values will be sent to the daemon\ninstead of accessing the files directly. If the connection cannot be established it\nwill fall back to direct file-access.  While this is convenient, it can silently\ncreate problems so please read the warning in the examples.\n\nFor a list of accepted formats, see the -l option in the rrdcached manual.\n\n{N | timestamp}:value[:value]...\nThe data used for updating the RRD was acquired at a certain time. This time can\neither be defined in seconds since 1970-01-01 or by using the letter 'N', in which\ncase the update time is set to be the current time. Negative time values are\nsubtracted from the current time. An ATSTYLE TIME SPECIFICATION (see the rrdfetch\ndocumentation) may also be used by delimiting the end of the time specification with\nthe '@' character instead of a ':'. Getting the timing right to the second is\nespecially important when you are working with data-sources of type COUNTER, DERIVE,\nDCOUNTER, DDERIVE or ABSOLUTE.\n\nWhen using negative time values, options and data have to be separated by two dashes\n(--), else the time value would be parsed as an option.  See below for an example.\n\nThe remaining elements of the argument are DS updates. The order of this list is the\nsame as the order the data sources were defined in the RRA. If there is no data for a\ncertain data-source, the letter U (e.g., N:0.1:U:1) can be specified.\n\nThe format of the value acquired from the data source is dependent on the data source\ntype chosen. Normally it will be numeric, but the data acquisition modules may impose\ntheir very own parsing of this parameter as long as the colon (:) remains the data\nsource value separator.\n",
            "subsections": []
        },
        "ENVIRONMENT VARIABLES": {
            "content": "The following environment variables may be used to change the behavior of \"rrdtool update\":\n\nRRDCACHEDADDRESS\nIf this environment variable is set it will have the same effect as specifying the\n\"--daemon\" option on the command line. If both are present, the command line argument\ntakes precedence.\n\nRRDCACHEDSTRIPPATH\nIf this environment variable is set it will strip the leading string from the filename\nprior to sending the filename to rrdcached.  This is mostly intended to allow rrdcached\nto work with xymon and cacti tools without having to modify those tools.\n",
            "subsections": []
        },
        "EXAMPLES": {
            "content": "•   \"rrdtool update demo1.rrd N:3.44:3.15:U:23\"\n\nUpdate the database file demo1.rrd with 3 known and one *UNKNOWN* value. Use the current\ntime as the update time.\n\n•   \"rrdtool update demo2.rrd 887457267:U 887457521:22 887457903:2.7\"\n\nUpdate the database file demo2.rrd which expects data from a single data-source, three\ntimes. First with an *UNKNOWN* value then with two regular readings. The update interval\nseems to be around 300 seconds.\n\n•   \"rrdtool update demo3.rrd -- -5:21 N:42\"\n\nUpdate the database file demo3.rrd two times, using five seconds in the past and the\ncurrent time as the update times.\n\n•   \"rrdtool update --daemon unix:/tmp/rrdd.sock demo4.rrd N:23\"\n\nUse the UNIX domain socket \"/tmp/rrdd.sock\" to contact the caching daemon. If the caching\ndaemon is not available, update the file \"demo4.rrd\" directly.  WARNING: Since a relative\npath is specified, the following disturbing effect may occur: If the daemon is available,\nthe file relative to the working directory of the daemon is used. If the daemon is not\navailable, the file relative to the current working directory of the invoking process is\nused.  This may update two different files depending on whether the daemon could be\nreached or not. Don't do relative paths, kids!\n",
            "subsections": []
        },
        "AUTHORS": {
            "content": "Tobias Oetiker <tobi@oetiker.ch>, Florian Forster <octo at verplant.org>\n\n\n\n1.7.2                                        2022-03-17                                 RRDUPDATE(1)",
            "subsections": []
        }
    },
    "summary": "rrdupdate - Store a new set of values into the RRD",
    "flags": [],
    "examples": [
        "•   \"rrdtool update demo1.rrd N:3.44:3.15:U:23\"",
        "Update the database file demo1.rrd with 3 known and one *UNKNOWN* value. Use the current",
        "time as the update time.",
        "•   \"rrdtool update demo2.rrd 887457267:U 887457521:22 887457903:2.7\"",
        "Update the database file demo2.rrd which expects data from a single data-source, three",
        "times. First with an *UNKNOWN* value then with two regular readings. The update interval",
        "seems to be around 300 seconds.",
        "•   \"rrdtool update demo3.rrd -- -5:21 N:42\"",
        "Update the database file demo3.rrd two times, using five seconds in the past and the",
        "current time as the update times.",
        "•   \"rrdtool update --daemon unix:/tmp/rrdd.sock demo4.rrd N:23\"",
        "Use the UNIX domain socket \"/tmp/rrdd.sock\" to contact the caching daemon. If the caching",
        "daemon is not available, update the file \"demo4.rrd\" directly.  WARNING: Since a relative",
        "path is specified, the following disturbing effect may occur: If the daemon is available,",
        "the file relative to the working directory of the daemon is used. If the daemon is not",
        "available, the file relative to the current working directory of the invoking process is",
        "used.  This may update two different files depending on whether the daemon could be",
        "reached or not. Don't do relative paths, kids!"
    ],
    "see_also": []
}