github.com/influxdata/telegraf@v1.30.3/docs/FAQ.md (about)

     1  # Frequently Asked Questions
     2  
     3  ## When is the next release? When will my PR or fix get released?
     4  
     5  Telegraf has four minor releases a year in March, June, September, and
     6  December. In between each of those minor releases, there are 2-4 bug fix
     7  releases that happen every 3 weeks.
     8  
     9  This [Google Calendar][] is kept up to date for upcoming releases dates.
    10  Additionally, users can look at the [GitHub milestones][] for the next minor
    11  and bug fix release.
    12  
    13  PRs that resolves issues are released in the next release. PRs that introduce
    14  new features are held for the next minor release. Users can view what
    15  [GitHub milestones][] a PR belongs to to determine the release it will go out
    16  with.
    17  
    18  [Google Calendar]: https://calendar.google.com/calendar/embed?src=c_1ikq7u4f5c4o6mh9ep4duo3avk%40group.calendar.google.com
    19  [GitHub milestones]: https://github.com/influxdata/telegraf/milestones
    20  
    21  ## How can I filter or select specific metrics?
    22  
    23  Telegraf has options to select certain metrics or tags as well as filter out
    24  specific tags or fields:
    25  
    26  - **Selectors** allow a user to include or exclude entire metrics based on the
    27    metric name or tag key/pair values.
    28  - **Modifiers** allow a user to remove tags and fields based on specific keys,
    29    with glob support.
    30  
    31  For more details and examples, see the [Metric Filtering][metric filtering]
    32  section in the docs.
    33  
    34  ## Could not find a usable config.yml, you may have revoked the CircleCI OAuth app
    35  
    36  This is an error from CircleCI during test runs.
    37  
    38  To resolve the error, you need to log back into CircleCI with your
    39  username/password if that is how you log in or if you use GitHub log, re-create
    40  your oauth/re-login with github.
    41  
    42  That should regenerate your token and then allow you to push a commit or close
    43  and reopen this PR and tests should run.
    44  
    45  ## What does "Context Deadline exceeded (Client.Timeout while awaiting headers)" mean?
    46  
    47  This is a generic error received from Go's HTTP client. It is generally the
    48  result of a network blip or hiccup as a result of a DNS, proxy, firewall,
    49  and/or other network issue.
    50  
    51  The error should be temporary and Telegraf will recover shortly after without
    52  the loss of data.
    53  
    54  ## How do I set the timestamp format for parsing data?
    55  
    56  Telegraf's `timestamp_format` config option requires the use
    57  [Go's reference time][go ref time] to correctly translate the timestamp. For
    58  example, if you have the time:
    59  
    60  ```s
    61  2023-03-01T00:00:42.586+0800
    62  ```
    63  
    64  A user needs the timestamp format:
    65  
    66  ```s
    67  2006-01-02T15:04:05.000-0700
    68  ```
    69  
    70  User's can try this out in the [Go playground][playground].
    71  
    72  [go ref time]: https://pkg.go.dev/time#pkg-constants
    73  [playground]: https://goplay.tools/snippet/hi9GIOG_gVQ
    74  
    75  ## Q: How can I monitor the Docker Engine Host from within a container?
    76  
    77  You will need to setup several volume mounts as well as some environment
    78  variables:
    79  
    80  ```shell
    81  docker run --name telegraf \
    82      -v /:/hostfs:ro \
    83      -e HOST_ETC=/hostfs/etc \
    84      -e HOST_PROC=/hostfs/proc \
    85      -e HOST_SYS=/hostfs/sys \
    86      -e HOST_VAR=/hostfs/var \
    87      -e HOST_RUN=/hostfs/run \
    88      -e HOST_MOUNT_PREFIX=/hostfs \
    89      telegraf
    90  ```
    91  
    92  ## Q: Why do I get a "no such host" error resolving hostnames that other programs can resolve?
    93  
    94  Go uses a pure Go resolver by default for [name resolution](https://golang.org/pkg/net/#hdr-Name_Resolution).
    95  This resolver behaves differently than the C library functions but is more
    96  efficient when used with the Go runtime.
    97  
    98  If you encounter problems or want to use more advanced name resolution methods
    99  that are unsupported by the pure Go resolver, you can switch to the cgo
   100  resolver.
   101  
   102  If running manually set:
   103  
   104  ```shell
   105  export GODEBUG=netdns=cgo
   106  ```
   107  
   108  If running as a service add the environment variable to `/etc/default/telegraf`:
   109  
   110  ```shell
   111  GODEBUG=netdns=cgo
   112  ```
   113  
   114  ## Q: How can I manage series cardinality?
   115  
   116  High [series cardinality][], when not properly managed, can cause high load on
   117  your database.  Telegraf attempts to avoid creating series with high
   118  cardinality, but some monitoring workloads such as tracking containers are are
   119  inherently high cardinality.  These workloads can still be monitored, but care
   120  must be taken to manage cardinality growth.
   121  
   122  You can use the following techniques to avoid cardinality issues:
   123  
   124  - Use [metric filtering][] options to exclude unneeded measurements and tags.
   125  - Write to a database with an appropriate [retention policy][].
   126  - Consider using the [Time Series Index][tsi].
   127  - Monitor your databases using the [show cardinality][] commands.
   128  - Consult the [InfluxDB documentation][influx docs] for the most up-to-date techniques.
   129  
   130  [series cardinality]: https://docs.influxdata.com/influxdb/v1.7/concepts/glossary/#series-cardinality
   131  [metric filtering]: https://github.com/influxdata/telegraf/blob/master/docs/CONFIGURATION.md#metric-filtering
   132  [retention policy]: https://docs.influxdata.com/influxdb/latest/guides/downsampling_and_retention/
   133  [tsi]: https://docs.influxdata.com/influxdb/latest/concepts/time-series-index/
   134  [show cardinality]: https://docs.influxdata.com/influxdb/latest/query_language/spec/#show-cardinality
   135  [influx docs]: https://docs.influxdata.com/influxdb/latest/