nixos/acme: Disable lego renew sleeping

Lego has a built-in mechanism for sleeping for a random amount
of time before renewing a certificate. In our environment this
is not only unnecessary (as our systemd timer takes care of it)
but also unwanted since it slows down the execution of the
systemd service encompassing it, thus also slowing down the
start up of any services its depending on.

Also added FixedRandomDelay to the timer for more predictability.

1 files changed, 2 insertions, 2 deletions

diff --git a/nixos/modules/security/acme/default.nix b/nixos/modules/security/acme/default.nix
index 91ec24ab1f58d..e9299fb1b3adb 100644
--- a/nixos/modules/security/acme/default.nix
+++ b/nixos/modules/security/acme/default.nix
@@ -190,7 +190,7 @@ let
     );
     renewOpts = escapeShellArgs (
       commonOpts
-      ++ [ "renew" ]
+      ++ [ "renew" "--no-random-sleep" ]
       ++ optionals data.ocspMustStaple [ "--must-staple" ]
       ++ data.extraLegoRenewFlags
     );
@@ -223,9 +223,9 @@ let
         # have many certificates, the renewals are distributed over
         # the course of the day to avoid rate limits.
         AccuracySec = "${toString (_24hSecs / numCerts)}s";
-
         # Skew randomly within the day, per https://letsencrypt.org/docs/integration-guide/.
         RandomizedDelaySec = "24h";
+        FixedRandomDelay = true;
       };
     };