Grafana supports automatic rendering of panels and dashboards as PNG images. This allows Grafana to automatically generate images of your panels to include in alert notifications.
When an image is being rendered the PNG-image is temporarily written to the file system. When an image is rendered, the PNG image is temporary written to the
png folder in the Grafana
A background job runs every 10 minutes and removes temporary images. You can configure how long an image should be stored before being removed by configuring the temp-data-lifetime setting.
You can also render a PNG by clicking the dropdown arrow next to a panel title, then clicking Share > Direct link rendered image.
Minimum free memory recommendation is 16GB on the system doing the rendering.
Rendering images can require a lot of memory, mainly because Grafana creates browser instances in the background for the actual rendering. If multiple images are rendered in parallel, then the rendering has a bigger memory footprint. One advantage of using the remote rendering service is that the rendering will be done on the remote system, so your local system resources will not be affected by rendering.
Alerting and render limits
Alert notifications can include images, but rendering many images at the same time can overload the server where the renderer is running. For instructions of how to configure this, see concurrent_render_limit.
Install Grafana Image Renderer plugin
The Grafana image renderer plugin is a plugin that runs on the backend and handles rendering panels and dashboards as PNG images using headless Chrome.
To install the plugin, refer to the Grafana Image Renderer Installation instructions.
Run in custom Grafana Docker image
We recommend setting up another Docker container for rendering and using remote rendering. Refer to Remote rendering service for instructions.
If you still want to install the plugin in the Grafana Docker image, refer to Build with Grafana Image Renderer plugin pre-installed.
Remote rendering service
Requires an internet connection.
The Grafana Image Renderer plugin can also be run as a remote HTTP rendering service. In this setup, Grafana renders an image by making a HTTP request to the remote rendering service, which in turn renders the image and returns it back in the HTTP response to Grafana.
You can run the remote HTTP rendering service using Docker or as a standalone Node.js application.
Run in Docker
The following example shows how to run Grafana and the remote HTTP rendering service in two separate Docker containers using Docker Compose.
docker-compose.yml with the following content:
version: '2' services: grafana: image: grafana/grafana:master ports: - "3000:3000" environment: GF_RENDERING_SERVER_URL: http://renderer:8081/render GF_RENDERING_CALLBACK_URL: http://grafana:3000/ GF_LOG_FILTERS: rendering:debug renderer: image: grafana/grafana-image-renderer:latest ports: - 8081
And then run:
Run as standalone Node.js application
The following example describes how to build and run the remote HTTP rendering service as a standalone Node.js application and configure Grafana appropriately.
- Clone the Grafana image renderer plugin Git repository.
Install dependencies and build:
yarn install --pure-lockfile yarn run build
- Run the server:
node build/app.js server --port=8081
Update Grafana configuration:
[rendering] server_url = http://localhost:8081/render callback_url = http://localhost:3000/
PhantomJS is deprecated since Grafana v6.4 and will be removed in a future release. Please migrate to the Grafana Image Renderer plugin or remote rendering service.
Troubleshoot image rendering
Enable debug log messages for rendering in the Grafana configuration file and inspect the Grafana server log.
[log] filters = rendering:debug
Grafana image renderer plugin and remote rendering service
The plugin and rendering service uses Chromium browser which depends on certain libraries. If you don’t have all of those libraries installed in your system you may encounter errors when trying to render an image, e.g.
Rendering failed: Error: Failed to launch chrome!/var/lib/grafana/plugins/grafana-image-renderer/chrome-linux/chrome: error while loading shared libraries: libX11.so.6: cannot open shared object file: No such file or directory\n\n\nTROUBLESHOOTING: https://github.com/GoogleChrome/puppeteer/blob/master/docs/troubleshooting.md
In general you can use the
ldd utility to figure out what shared libraries
are not installed in your system:
cd <grafana-image-render plugin directory> ldd chrome-linux/chrome linux-vdso.so.1 (0x00007fff1bf65000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f2047945000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f2047924000) librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f204791a000) libX11.so.6 => not found libX11-xcb.so.1 => not found libxcb.so.1 => not found libXcomposite.so.1 => not found ...
On Ubuntu 18.10 the following dependencies have been confirmed as needed for the image rendering to function.
libx11-6 libx11-xcb1 libxcomposite1 libxcursor1 libxdamage1 libxext6 libxfixes3 libxi6 libxrender1 libxtst6 libglib2.0-0 libnss3 libcups2 libdbus-1-3 libxss1 libxrandr2 libgtk-3-0 libgtk-3-0 libasound2
On a minimal Centos install the following dependencies have been confirmed as needed for the image rendering to function:
libXcomposite libXdamage libXtst cups libXScrnSaver pango atk adwaita-cursor-theme adwaita-icon-theme at at-spi2-atk at-spi2-core cairo-gobject colord-libs dconf desktop-file-utils ed emacs-filesystem gdk-pixbuf2 glib-networking gnutls gsettings-desktop-schemas gtk-update-icon-cache gtk3 hicolor-icon-theme jasper-libs json-glib libappindicator-gtk3 libdbusmenu libdbusmenu-gtk3 libepoxy liberation-fonts liberation-narrow-fonts liberation-sans-fonts liberation-serif-fonts libgusb libindicator-gtk3 libmodman libproxy libsoup libwayland-cursor libwayland-egl libxkbcommon m4 mailx nettle patch psmisc redhat-lsb-core redhat-lsb-submod-security rest spax time trousers xdg-utils xkeyboard-config
Certificate signed by internal certificate authorities
In many cases Grafana, runs on internal servers and uses certificates that have not been signed by a CA (Certificate Authority) known to Chrome, and therefore cannot be validated. Chrome internally uses NSS (Network Security Services) for cryptogtraphic operations such as the validation of certificates.
If you are using the Grafana Image Renderer with a Grafana server that uses a certificate signed by such a custom CA (for example a company-internal CA), rendering images will fail and you will see messages like this in the Grafana log:
t=2019-12-04T12:39:22+0000 lvl=error msg="Render request failed" logger=rendering error=map url="https://192.168.106.101:3443/d-solo/zxDJxNaZk/graphite-metrics?orgId=1&refresh=1m&from=1575438321300&to=1575459921300&var-Host=master1&panelId=4&width=1000&height=500&tz=Europe%2FBerlin&render=1" timestamp=0001-01-01T00:00:00.000Z t=2019-12-04T12:39:22+0000 lvl=error msg="Rendering failed." logger=context userId=1 orgId=1 uname=admin error="Rendering failed: Error: net::ERR_CERT_AUTHORITY_INVALID at https://192.168.106.101:3443/d-solo/zxDJxNaZk/graphite-metrics?orgId=1&refresh=1m&from=1575438321300&to=1575459921300&var-Host=master1&panelId=4&width=1000&height=500&tz=Europe%2FBerlin&render=1" t=2019-12-04T12:39:22+0000 lvl=error msg="Request Completed" logger=context userId=1 orgId=1 uname=admin method=GET path=/render/d-solo/zxDJxNaZk/graphite-metrics status=500 remote_addr=192.168.106.101 time_ms=310 size=1722 referer="https://grafana.xxx-xxx/d/zxDJxNaZk/graphite-metrics?orgId=1&refresh=1m"
error in the above messages might be misspelled with a single
If this happens, then you have to add the certificate to the trust store. If you have the certificate file for the internal root CA in the file
internal-root-ca.crt.pem, then use these commands to create a user specific NSS trust store for the Grafana user (
grafana for the purpose of this example) and execute the following steps:
[root@merver ~]# certutil -d sql:/usr/share/grafana/.pki/nssdb -A -n internal-root-ca -t C -i /etc/pki/tls/certs/internal-root-ca.crt.pem [root@server ~]# chown -R grafana: /usr/share/grafana/.pki/nssdb
Please note that this is not recommended, since you may encounter problems if the installed version of Chrome/Chromium is not compatible with the Grafana Image renderer plugin.
To override the path to the Chrome/Chromium executable, set an environment variable and make sure that it’s available for the Grafana process. For example: