diff --git a/data_safe_haven/infrastructure/programs/sre/networking.py b/data_safe_haven/infrastructure/programs/sre/networking.py
index 1f33c52082..5419021472 100644
--- a/data_safe_haven/infrastructure/programs/sre/networking.py
+++ b/data_safe_haven/infrastructure/programs/sre/networking.py
@@ -1454,6 +1454,7 @@ def __init__(
         subnet_data_configuration_name = "DataConfigurationSubnet"
         subnet_data_desired_state_name = "DataDesiredStateSubnet"
         subnet_data_private_name = "DataPrivateSubnet"
+        # subnet_external_git_mirror_name = "ExternalGitMirrorSubnet"
         subnet_firewall_name = "AzureFirewallSubnet"
         subnet_firewall_management_name = "AzureFirewallManagementSubnet"
         subnet_guacamole_containers_name = "GuacamoleContainersSubnet"