Update troubleshoot-resource-bridge.md

Author: alt-key

articles/azure-arc/resource-bridge/troubleshoot-resource-bridge.md

@@ -143,7 +143,23 @@ Be sure that the proxy server on your management machine trusts both the SSL cer
 
 ### No such host - dp.kubernetesconfiguration.azure.com
 
-If you receive an error that contains `dial tcp: lookup westeurope.dp.kubernetesconfiguration.azure.com: no such host` while deploying Arc resource bridge, this means that the configuration dataplane is currently unavailable in the specified region. The service may be temporarily unavailable. Please wait for the service to be available and then retry the deployment.
+An error that contains `dial tcp: lookup westeurope.dp.kubernetesconfiguration.azure.com: no such host` while deploying Arc resource bridge means that the configuration dataplane is currently unavailable in the specified region. The service may be temporarily unavailable. Please wait for the service to be available and then retry the deployment.
+
+### No such host for Arc resource bridge required URL
+
+An error that contains an Arc resource bridge required URL with the message `no such host` indicates that DNS is not able to resolve the URL. The error may look similar to the example below, where the required URL is `https://msk8s.api.cdp.microsoft.com`:
+
+`Error:  { _errorCode_: _InvalidEntityError_, _errorResponse_: _{\n\_message\_: \_Post \\\_https://msk8s.api.cdp.microsoft.com/api/v1.1/contents/default/namespaces/default/names/arc-appliance-stable-catalogs-ext/versions/latest?action=select\\\_: POST https://msk8s.api.cdp.microsoft.com/api/v1.1/contents/default/namespaces/default/names/arc-appliance-stable-catalogs-ext/versions/latest?action=select giving up after 6 attempt(s): Post \\\_https://msk8s.api.cdp.microsoft.com/api/v1.1/contents/default/namespaces/default/names/arc-appliance-stable-catalogs-ext/versions/latest?action=select\\\_: proxyconnect tcp: dial tcp: lookup http: no such host\_\n}_ }`
+
+This error can occur if the DNS settings provided during deployment are not correct or there is a problem with the DNS server(s). You can check if your DNS server is able to resolve the url by running the following command from the management machine or a machine that has access to the DNS server(s): 
+
+```
+nslookup
+> set debug
+> <hostname> <DNS server IP>
+```
+
+In order to resolve the error, your DNS server(s) must be configured to resolve all Arc resource bridge required URLs and the DNS server(s) should be correctly provided during deployment of Arc resource bridge.
 
 ### KVA timeout error