Important: This documentation is about an older version. It's relevant only to the release noted, many of the features and functions have been updated or replaced. Please view the current version.
LogCLI, Grafana Loki’s command-line interface
LogCLI is the command-line interface to Grafana Loki. It facilitates running LogQL queries against a Loki instance.
Installation
Binary (Recommended)
Download the logcli
binary from the
Loki releases page.
Build LogCLI from source
Clone the Loki repository and build logcli
from source:
git clone https://github.com/grafana/loki.git
cd loki
make logcli
Optionally, move the binary into a directory that is part of your $PATH
.
cp cmd/logcli/logcli /usr/local/bin/logcli
LogCLI usage
Grafana Cloud example
If you are running on Grafana Cloud, use:
export LOKI_ADDR=https://logs-us-west1.grafana.net
export LOKI_USERNAME=<username>
export LOKI_PASSWORD=<password>
Otherwise you can point LogCLI to a local instance directly without needing a username and password:
export LOKI_ADDR=http://localhost:3100
Note: If you are running Loki behind a proxy server and you have authentication configured, you will also have to pass in LOKI_USERNAME and LOKI_PASSWORD, LOKI_BEARER_TOKEN or LOKI_BEARER_TOKEN_FILE accordingly.
$ logcli labels job
https://logs-dev-ops-tools1.grafana.net/api/prom/label/job/values
cortex-ops/consul
cortex-ops/cortex-gw
...
$ logcli query '{job="cortex-ops/consul"}'
https://logs-dev-ops-tools1.grafana.net/api/prom/query?query=%7Bjob%3D%22cortex-ops%2Fconsul%22%7D&limit=30&start=1529928228&end=1529931828&direction=backward®exp=
Common labels: {job="cortex-ops/consul", namespace="cortex-ops"}
2018-06-25T12:52:09Z {instance="consul-8576459955-pl75w"} 2018/06/25 12:52:09 [INFO] raft: Snapshot to 475409 complete
2018-06-25T12:52:09Z {instance="consul-8576459955-pl75w"} 2018/06/25 12:52:09 [INFO] raft: Compacting logs from 456973 to 465169
...
$ logcli series -q --match='{namespace="loki",container_name="loki"}'
{app="loki", container_name="loki", controller_revision_hash="loki-57c9df47f4", filename="/var/log/pods/loki_loki-0_8ed03ded-bacb-4b13-a6fe-53a445a15887/loki/0.log", instance="loki-0", job="loki/loki", name="loki", namespace="loki", release="loki", statefulset_kubernetes_io_pod_name="loki-0", stream="stderr"}
Batched queries
LogCLI sends queries to Loki such that query results arrive in batches.
The --limit
option for a logcli query
command caps the quantity of
log lines for a single query.
When not set, --limit
defaults to 30.
The limit protects the user from overwhelming the system
for cases in which the specified query would have returned a large quantity
of log lines.
The limit also protects the user from unexpectedly large responses.
The quantity of log line results that arrive in each batch
is set by the --batch
option in a logcli query
command.
When not set, --batch
defaults to 1000.
Setting a --limit
value larger than the --batch
value causes the
requests from LogCLI to Loki to be batched.
Loki has a server-side limit that defaults to 5000 for the maximum quantity
of lines returned for a single query.
The batching of requests allows you to query for a results set that
is larger than the server-side limit,
as long as the --batch
value is less than the server limit.
Query metadata is output to stderr
for each batch.
Set the --quiet
option on the logcli query
command line to suppress
the output of the query metadata.
Configuration
Configuration values are considered in the following order (lowest to highest):
- Environment variables
- Command-line options
LogCLI command reference
The output of logcli help
:
usage: logcli [<flags>] <command> [<args> ...]
A command-line for loki.
Flags:
--help Show context-sensitive help (also try --help-long and
--help-man).
--version Show application version.
-q, --quiet Suppress query metadata
--stats Show query statistics
-o, --output=default Specify output mode [default, raw, jsonl]. raw
suppresses log labels and timestamp.
-z, --timezone=Local Specify the timezone to use when formatting output
timestamps [Local, UTC]
--cpuprofile="" Specify the location for writing a CPU profile.
--memprofile="" Specify the location for writing a memory profile.
--stdin Take input logs from stdin
--addr="http://localhost:3100"
Server address. Can also be set using LOKI_ADDR env
var.
--username="" Username for HTTP basic auth. Can also be set using
LOKI_USERNAME env var.
--password="" Password for HTTP basic auth. Can also be set using
LOKI_PASSWORD env var.
--ca-cert="" Path to the server Certificate Authority. Can also be
set using LOKI_CA_CERT_PATH env var.
--tls-skip-verify Server certificate TLS skip verify.
--cert="" Path to the client certificate. Can also be set using
LOKI_CLIENT_CERT_PATH env var.
--key="" Path to the client certificate key. Can also be set
using LOKI_CLIENT_KEY_PATH env var.
--org-id="" adds X-Scope-OrgID to API requests for representing
tenant ID. Useful for requesting tenant data when
bypassing an auth gateway.
Commands:
help [<command>...]
Show help.
query [<flags>] <query>
Run a LogQL query.
The "query" command is useful for querying for logs. Logs can be returned in
a few output modes:
raw: log line
default: log timestamp + log labels + log line
jsonl: JSON response from Loki API of log line
The output of the log can be specified with the "-o" flag, for example, "-o
raw" for the raw output format.
The "query" command will output extra information about the query and its
results, such as the API URL, set of common labels, and set of excluded
labels. This extra information can be suppressed with the --quiet flag.
By default we look over the last hour of data; use --since to modify or
provide specific start and end times with --from and --to respectively.
Notice that when using --from and --to then ensure to use RFC3339Nano time
format, but without timezone at the end. The local timezone will be added
automatically or if using --timezone flag.
Example:
logcli query
--timezone=UTC
--from="2021-01-19T10:00:00Z"
--to="2021-01-19T20:00:00Z"
--output=jsonl
'my-query'
The output is limited to 30 entries by default; use --limit to increase.
While "query" does support metrics queries, its output contains multiple
data points between the start and end query time. This output is used to
build graphs, similar to what is seen in the Grafana Explore graph view. If
you are querying metrics and just want the most recent data point (like what
is seen in the Grafana Explore table view), then you should use the
"instant-query" command instead.
instant-query [<flags>] <query>
Run an instant LogQL query.
The "instant-query" command is useful for evaluating a metric query for a
single point in time. This is equivalent to the Grafana Explore table view;
if you want a metrics query that is used to build a Grafana graph, you
should use the "query" command instead.
This command does not produce useful output when querying for log lines; you
should always use the "query" command when you are running log queries.
For more information about log queries and metric queries, refer to the
LogQL documentation:
https://grafana.com/docs/loki/latest/logql/
labels [<flags>] [<label>]
Find values for a given label.
series [<flags>] <matcher>
Run series query.
The "series" command will take the provided label matcher and return all the
log streams found in the time window.
It is possible to send an empty label matcher '{}' to return all streams.
Use the --analyze-labels flag to get a summary of the labels found in all
streams. This is helpful to find high cardinality labels.
LogCLI query command reference
The output of logcli help query
:
usage: logcli query [<flags>] <query>
Run a LogQL query.
The "query" command is useful for querying for logs. Logs can be returned in a
few output modes:
raw: log line
default: log timestamp + log labels + log line
jsonl: JSON response from Loki API of log line
The output of the log can be specified with the "-o" flag, for example, "-o raw"
for the raw output format.
The "query" command will output extra information about the query and its
results, such as the API URL, set of common labels, and set of excluded labels.
This extra information can be suppressed with the --quiet flag.
By default we look over the last hour of data; use --since to modify or provide
specific start and end times with --from and --to respectively.
Notice that when using --from and --to then ensure to use RFC3339Nano time
format, but without timezone at the end. The local timezone will be added
automatically or if using --timezone flag.
Example:
logcli query
--timezone=UTC
--from="2021-01-19T10:00:00Z"
--to="2021-01-19T20:00:00Z"
--output=jsonl
'my-query'
The output is limited to 30 entries by default; use --limit to increase.
While "query" does support metrics queries, its output contains multiple data
points between the start and end query time. This output is used to build
graphs, similar to what is seen in the Grafana Explore graph view. If you are
querying metrics and just want the most recent data point (like what is seen in
the Grafana Explore table view), then you should use the "instant-query" command
instead.
Flags:
--help Show context-sensitive help (also try --help-long and
--help-man).
--version Show application version.
-q, --quiet Suppress query metadata
--stats Show query statistics
-o, --output=default Specify output mode [default, raw, jsonl]. raw
suppresses log labels and timestamp.
-z, --timezone=Local Specify the timezone to use when formatting output
timestamps [Local, UTC]
--cpuprofile="" Specify the location for writing a CPU profile.
--memprofile="" Specify the location for writing a memory profile.
--stdin Take input logs from stdin
--addr="http://localhost:3100"
Server address. Can also be set using LOKI_ADDR env
var.
--username="" Username for HTTP basic auth. Can also be set using
LOKI_USERNAME env var.
--password="" Password for HTTP basic auth. Can also be set using
LOKI_PASSWORD env var.
--ca-cert="" Path to the server Certificate Authority. Can also be
set using LOKI_CA_CERT_PATH env var.
--tls-skip-verify Server certificate TLS skip verify.
--cert="" Path to the client certificate. Can also be set using
LOKI_CLIENT_CERT_PATH env var.
--key="" Path to the client certificate key. Can also be set
using LOKI_CLIENT_KEY_PATH env var.
--org-id="" adds X-Scope-OrgID to API requests for representing
tenant ID. Useful for requesting tenant data when
bypassing an auth gateway.
--limit=30 Limit on number of entries to print.
--since=1h Lookback window.
--from=FROM Start looking for logs at this absolute time
(inclusive)
--to=TO Stop looking for logs at this absolute time
(exclusive)
--step=STEP Query resolution step width, for metric queries.
Evaluate the query at the specified step over the
time range.
--interval=INTERVAL Query interval, for log queries. Return entries at
the specified interval, ignoring those between.
**This parameter is experimental, please see Issue
1779**
--batch=1000 Query batch size to use until 'limit' is reached
--forward Scan forwards through logs.
--no-labels Do not print any labels
--exclude-label=EXCLUDE-LABEL ...
Exclude labels given the provided key during output.
--include-label=INCLUDE-LABEL ...
Include labels given the provided key during output.
--labels-length=0 Set a fixed padding to labels
--store-config="" Execute the current query using a configured storage
from a given Loki configuration file.
--colored-output Show output with colored labels
-t, --tail Tail the logs
-f, --follow Alias for --tail
--delay-for=0 Delay in tailing by number of seconds to accumulate
logs for re-ordering
Args:
<query> eg '{foo="bar",baz=~".*blip"} |~ ".*error.*"'
LogCLI labels command reference
The output of logcli help labels
:
usage: logcli labels [<flags>] [<label>]
Find values for a given label.
Flags:
--help Show context-sensitive help (also try --help-long and
--help-man).
--version Show application version.
-q, --quiet Suppress query metadata
--stats Show query statistics
-o, --output=default Specify output mode [default, raw, jsonl]. raw
suppresses log labels and timestamp.
-z, --timezone=Local Specify the timezone to use when formatting output
timestamps [Local, UTC]
--cpuprofile="" Specify the location for writing a CPU profile.
--memprofile="" Specify the location for writing a memory profile.
--stdin Take input logs from stdin
--addr="http://localhost:3100"
Server address. Can also be set using LOKI_ADDR env
var.
--username="" Username for HTTP basic auth. Can also be set using
LOKI_USERNAME env var.
--password="" Password for HTTP basic auth. Can also be set using
LOKI_PASSWORD env var.
--ca-cert="" Path to the server Certificate Authority. Can also be
set using LOKI_CA_CERT_PATH env var.
--tls-skip-verify Server certificate TLS skip verify.
--cert="" Path to the client certificate. Can also be set using
LOKI_CLIENT_CERT_PATH env var.
--key="" Path to the client certificate key. Can also be set
using LOKI_CLIENT_KEY_PATH env var.
--org-id="" adds X-Scope-OrgID to API requests for representing
tenant ID. Useful for requesting tenant data when
bypassing an auth gateway.
--since=1h Lookback window.
--from=FROM Start looking for labels at this absolute time
(inclusive)
--to=TO Stop looking for labels at this absolute time
(exclusive)
Args:
[<label>] The name of the label.
LogCLI series command reference
The output of logcli help series
:
usage: logcli series [<flags>] <matcher>
Run series query.
The "series" command will take the provided label matcher and return all the log
streams found in the time window.
It is possible to send an empty label matcher '{}' to return all streams.
Use the --analyze-labels flag to get a summary of the labels found in all
streams. This is helpful to find high cardinality labels.
Flags:
--help Show context-sensitive help (also try --help-long and
--help-man).
--version Show application version.
-q, --quiet Suppress query metadata
--stats Show query statistics
-o, --output=default Specify output mode [default, raw, jsonl]. raw
suppresses log labels and timestamp.
-z, --timezone=Local Specify the timezone to use when formatting output
timestamps [Local, UTC]
--cpuprofile="" Specify the location for writing a CPU profile.
--memprofile="" Specify the location for writing a memory profile.
--stdin Take input logs from stdin
--addr="http://localhost:3100"
Server address. Can also be set using LOKI_ADDR env
var.
--username="" Username for HTTP basic auth. Can also be set using
LOKI_USERNAME env var.
--password="" Password for HTTP basic auth. Can also be set using
LOKI_PASSWORD env var.
--ca-cert="" Path to the server Certificate Authority. Can also be
set using LOKI_CA_CERT_PATH env var.
--tls-skip-verify Server certificate TLS skip verify.
--cert="" Path to the client certificate. Can also be set using
LOKI_CLIENT_CERT_PATH env var.
--key="" Path to the client certificate key. Can also be set
using LOKI_CLIENT_KEY_PATH env var.
--org-id="" adds X-Scope-OrgID to API requests for representing
tenant ID. Useful for requesting tenant data when
bypassing an auth gateway.
--since=1h Lookback window.
--from=FROM Start looking for logs at this absolute time
(inclusive)
--to=TO Stop looking for logs at this absolute time (exclusive)
--analyze-labels Printout a summary of labels including count of label
value combinations, useful for debugging high
cardinality series
Args:
<matcher> eg '{foo="bar",baz=~".*blip"}'
LogCLI --stdin
usage
You can consume log lines from your stdin
instead of Loki servers.
Say you have log files in your local, and just want to do run some LogQL queries for that, --stdin
flag can help.
NOTE: Currently it doesn’t support any type of metric queries
You may have to use stdin
flag for several reasons
- Quick way to check and validate a LogQL expressions.
- Learn basics of LogQL with just Log files and
LogCLI
tool ( without needing set up Loki servers, Grafana etc.) - Easy discussion on public forums. Like Q&A, Share the LogQL expressions.
NOTES on Usage
--limits
flag doesn’t have any meaning when using--stdin
(use pager likeless
for that)- Be aware there are no labels when using
--stdin
- So stream selector in the query is optional e.g just
|="timeout"|logfmt|level="error"
is same as{foo="bar"}|="timeout|logfmt|level="error"
- So stream selector in the query is optional e.g just
Examples
- Line filter -
cat mylog.log | logcli --stdin query '|="too many open connections"'
- Label matcher -
echo 'msg="timeout happened" level="warning"' | logcli --stdin query '|logfmt|level="warning"'
- Different parsers (logfmt, json, pattern, regexp) -
cat mylog.log | logcli --stdin query '|pattern <ip> - - <_> "<method> <uri> <_>" <status> <size> <_> "<agent>" <_>'
- Line formatters -
cat mylog.log | logcli --stdin query '|logfmt|line_format "{{.query}} {{.duration}}"'