diff --git a/nixos/tests/libreswan.nix b/nixos/tests/libreswan.nix
index ff3d2344a679..aadba941fab1 100644
--- a/nixos/tests/libreswan.nix
+++ b/nixos/tests/libreswan.nix
@@ -107,6 +107,8 @@ in
 
       with subtest("Network is up"):
           alice.wait_until_succeeds("ping -c1 bob")
+          alice.succeed("systemctl restart ipsec")
+          bob.succeed("systemctl restart ipsec")
 
       with subtest("Eve can eavesdrop cleartext traffic"):
           eavesdrop()
diff --git a/pkgs/tools/networking/libreswan/default.nix b/pkgs/tools/networking/libreswan/default.nix
index 47838f756635..a8e0dccdd2bb 100644
--- a/pkgs/tools/networking/libreswan/default.nix
+++ b/pkgs/tools/networking/libreswan/default.nix
@@ -89,6 +89,11 @@ stdenv.mkDerivation rec {
         -e 's|systemd-tmpfiles|true|g' \
         -i initsystems/systemd/Makefile
 
+    # Fix systemd detection on NixOS
+    sed -e 's|\(-a ! -x /bin/journalctl\)|\1 -a ! -x /run/current-system/sw/bin/journalctl|g' \
+        -e 's|\(-o ! -x /bin/journalctl\)|\1 -o ! -x /run/current-system/sw/bin/journalctl|g' \
+        -i programs/barf/barf.in
+
     # Fix the ipsec program from crushing the PATH
     sed -e 's|\(PATH=".*"\):.*$|\1:$PATH|' -i programs/ipsec/ipsec.in