diff --git a/doc/020_installation.rst b/doc/020_installation.rst
index 4d591356d..b53c350b1 100644
--- a/doc/020_installation.rst
+++ b/doc/020_installation.rst
@@ -265,6 +265,10 @@ binary, you can get it with `docker pull` like this:
 
     $ docker pull restic/restic
 
+Restic relies on the hostname for various operations. Make sure to set a static
+hostname using `--hostname` when creating a Docker container, otherwise Docker
+will assign a random hostname each time.
+
 From Source
 ***********
 
diff --git a/docker/README.md b/docker/README.md
index 1c2c9205c..444aae3dc 100644
--- a/docker/README.md
+++ b/docker/README.md
@@ -16,9 +16,13 @@ Set environment variable `RESTIC_REPOSITORY` and map volume to directories and
 files like:
 
 ```
-docker run --rm -ti \
+docker run --rm --hostname my-host -ti \
     -v $HOME/.restic/passfile:/pass \
     -v $HOME/importantdirectory:/data \
     -e RESTIC_REPOSITORY=rest:https://user:pass@hostname/ \
     restic/restic -p /pass backup /data
 ```
+
+Restic relies on the hostname for various operations. Make sure to set a static
+hostname using `--hostname` when creating a Docker container, otherwise Docker
+will assign a random hostname each time.