#33955·angular-cli

Can't use an array of hostnames in --allowedHosts cli parameter in @angular/build:dev-server

Author: silverhamCreated Aug 28, 2026Updated Aug 28, 2026
Labelsarea: @angular/buildgemini-triaged

Command

serve

Is this a regression?

  • Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

When using @angular-devkit/build-angular:dev-server I can use --allowedHosts parameter with array of hostnames, so my hostnames can be dynamic.

But when using @angular/build:dev-server the array of names is not recognized (only boolean type is passed instead?)

bash
ng serve myproject --allowed-hosts "example.com"

"Error: Unknown argument: example.com"

Workaround:

bash
__VITE_ADDITIONAL_SERVER_ALLOWED_HOSTS=example.com ng serve myproject

or hard code in the array format in angular.json like mentioned in https://github.com/angular/angular/issues/64104

Comparing the two builder i can see this difference if you "patch" @angular/build:dev-server's schema.json, then the command will work.

https://github.com/angular/angular-cli/blob/main/packages/angular_devkit/build_angular/src/builders/dev-server/schema.json vs https://github.com/angular/angular-cli/blob/main/packages/angular/build/src/builders/dev-server/schema.json

diff
    "allowedHosts": {
+     "type": "array",
      "description": "The hosts that the development server will respond to. This option sets the Vite option of the same name. For further details: https://vite.dev/config/server-options.html#server-allowedhosts",
      "default": [],
+      "items": {
+        "type": "string"
+      }
-      "oneOf": [
-        {
-          "type": "array",
-          "description": "A list of hosts that the development server will respond to.",
-          "items": {
-            "type": "string"
-          }
-        },
-        {
-          "type": "boolean",
-          "description": "Indicates that all hosts are allowed. This is not recommended and a security risk."
-        }
-      ]
    },

@see issue * PR for the devkit commit that added the option:

It note that @angular-devkit/build-angular:dev-server also has a (custom?) --disableHostCheck parameter which sets allowedHosts to true if passed, so then disable all hosts situation can be covered as schema no longer allows boolean, only array.

Not sure how to fix properly.

Minimal Reproduction

Exception or Error

Your Environment

-

Anything else relevant?

No response