services.openssh.knownHosts.*.publicKey: Update description and add example

Note that it's no longer allowed to have multiple public keys
separated by a newline.

1 files changed, 2 insertions, 3 deletions

diff --git a/nixos/modules/services/networking/ssh/sshd.nix b/nixos/modules/services/networking/ssh/sshd.nix
index bc89ea2d3cd..4be2b5fe0c0 100644
--- a/nixos/modules/services/networking/ssh/sshd.nix
+++ b/nixos/modules/services/networking/ssh/sshd.nix
@@ -244,13 +244,12 @@ in
           publicKey = mkOption {
             default = null;
             type = types.nullOr types.str;
+            example = "ecdsa-sha2-nistp521 AAAAE2VjZHN...UEPg==";
             description = ''
               The public key data for the host. You can fetch a public key
               from a running SSH server with the <command>ssh-keyscan</command>
               command. The public key should not include any host names, only
-              the key type and the key itself. It is allowed to add several
-              lines here, each line will be treated as type/key pair and the
-              host names will be prepended to each line.
+              the key type and the key itself.
             '';
           };
           publicKeyFile = mkOption {