RRDXPORT(1) rrdtool RRDXPORT(1)
NAME
rrdxport - Export data in XML format based on data from one or several
RRD
SYNOPSIS
rrdtool xport [-s|--startseconds] [-e|--endseconds] [-m|--maxrowsrows]
[--stepvalue] [--json] [-t|--showtime] [--enumds] [--daemon|-daddress]
[DEF:vname=rrd:ds-name:CF] [CDEF:vname=rpn-expression]
[XPORT:vname[:legend]]
DESCRIPTION
The xport function's main purpose is to write an XML formatted
representation of the data stored in one or several RRDs. It can also
extract numerical reports.
If no XPORT statements are found, there will be no output.
-s|--start seconds (default end-1day)
The time when the exported range should begin. Time in seconds
since epoch (1970-01-01) is required. Negative numbers are relative
to the current time. By default one day worth of data will be
printed. See also "AT-STYLE TIME SPECIFICATION" in rrdfetch for a
detailed explanation on how to specify time.
See "OUTPUT FORMAT" below for details on how this affects the
output.
-e|--end seconds (default now)
The time when the exported range should end. Time in seconds since
epoch. See also "AT-STYLE TIME SPECIFICATION" in rrdfetch for a
detailed explanation on how to specify time.
See "OUTPUT FORMAT" below for details on how this affects the
output.
-m|--maxrows rows (default 400 rows)
This works like the -w|--width parameter of rrdgraph. In fact it
is exactly the same, but the parameter was renamed to describe its
purpose in this module. See rrdgraph documentation for details.
--step value (default automatic)
See rrdgraph documentation.
--daemon|-d address
Address of the rrdcached daemon. If specified, a "flush" command is
sent to the server before reading the RRD files. This allows
rrdtool to return fresh data even if the daemon is configured to
cache values for a long time. For a list of accepted formats, see
the -l option in the rrdcached manual.
rrdtool xport --daemon unix:/var/run/rrdcached.sock ...
-t|--showtime
include the time into each data row.
--json
produce json formatted output (instead of xml)
--enumds
The generated xml should contain the data values in enumerated
tags.
<v0>val</v0><v1>val</v1>
DEF:vname=rrd:ds-name:CF
See rrdgraph documentation.
CDEF:vname=rpn-expression
See rrdgraph documentation.
XPORT:vname[:legend]
At least one XPORT statement should be present. The values
referenced by vname are printed. Optionally add a legend.
OUTPUT FORMAT
The output is enclosed in an xport element and contains two blocks. The
first block is enclosed by a meta element and contains some meta data.
The second block is enclosed by a data element and contains the data
rows.
Let's assume that the xport command looks like this:
rrdtool xport \
--start now-1h --end now \
DEF:xx=host-inout.lo.rrd:output:AVERAGE \
DEF:yy=host-inout.lo.rrd:input:AVERAGE \
CDEF:aa=xx,yy,+,8,* \
XPORT:xx:"out bytes" \
XPORT:aa:"in and out bits"
The resulting meta data section is (the values will depend on the RRD
characteristics):
<meta>
<start>1020611700</start>
<step>300</step>
<end>1020615600</end>
<rows>14</rows>
<columns>2</columns>
<legend>
<entry>out bytes</entry>
<entry>in and out bits</entry>
</legend>
</meta>
The resulting data section is:
<data>
<row><t>1020611700</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020612000</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020612300</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020612600</t><v>3.4113333333e+00</v><v>5.4581333333e+01</v></row>
<row><t>1020612900</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020613200</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020613500</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020613800</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020614100</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020614400</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020614700</t><v>3.7333333333e+00</v><v>5.9733333333e+01</v></row>
<row><t>1020615000</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020615300</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
<row><t>1020615600</t><v>NaN</v><v>NaN</v></row>
</data>
All the statistics in the output will use the same step. The first
sample will be the first sample starting immediately after --start. The
last sample will be the one ending at or immediately after --end.
Each sample has a timestamp and one or more values. The timestamps
associated with a value in RRDtool ALWAYS represent the time the sample
was taken. Since any value you sample will represent some sort of past
state your sampling apparatus has gathered, the timestamp will always
be at the end of the sampling period.
RRDtool does not store the actual samples, but does internal resampling
of the values presented to it. Nevertheless when a data value is
presented with a single timestamp the timestamp is at the end of the
period the value represents. Note that the timestamp itself is outside
the period the sample is valid for. For more details about this, see
PDP calculation explanation.
So the time range for a sample with a timestamp is actually from
"timestamp - step" inclusive to "timestamp" exclusive.
The first line of the sample output:
<row><t>1020611700</t><v>3.4000000000e+00</v><v>5.4400000000e+01</v></row>
therefore means that the values for the interval 1020611400 to
1020611699 were 3.4 and 54.4 for "out bytes" and "in and out bits"
respectively, because the value was taken at 1020611700.
EXAMPLE 1
rrdtool xport \
DEF:out=if1-inouts.rrd:outoctets:AVERAGE \
XPORT:out:"out bytes"
EXAMPLE 2
rrdtool xport \
DEF:out1=if1-inouts.rrd:outoctets:AVERAGE \
DEF:out2=if2-inouts.rrd:outoctets:AVERAGE \
CDEF:sum=out1,out2,+ \
XPORT:out1:"if1 out bytes" \
XPORT:out2:"if2 out bytes" \
XPORT:sum:"output sum"
ENVIRONMENT VARIABLES
The following environment variables may be used to change the behavior
of "rrdtoolxport":
RRDCACHED_ADDRESS
If this environment variable is set it will have the same effect as
specifying the "--daemon" option on the command line. If both are
present, the command line argument takes precedence.
AUTHOR
Tobias Oetiker <tobi@oetiker.ch>
1.7.2 2020-04-11 RRDXPORT(1)