ZVM Cannot Connect or Authenticate to vCD/AMQP – Basic Troublehsooting

KB Number:
000001248

Symptoms:

While attempting to configure Zerto Virtual Replication to replicate to vCD, there might be connectivity issues that prevent ZVM from communicating with vCD. This problem can occur:

  • While attempting to install AMQP

  • While attempting to install Zerto Virtual Replication and enable the vCD option

  • While configuring Zerto Virtual Replication to connect to vCD, after losing connectivity

This article outlines the troubleshooting steps to solve this disconnect.


Solution:

To troubleshoot the connection between the ZVM and vCD, verify the following:

  • Verify that from the ZVM, you can ping the vCD IP address and resolve the DNS name.

  • Verify that TCP port 443 is open between the ZVM and vCD.

  • Verify that the Windows FireWall is down on the Windows machine on which the ZVM runs (the windows machine on which Zerto Virtual Replication is installed). If it is running it might block the needed connections.

  • Open Internet Explorer on the ZVM machine and attempt to get to the vCD address.

  • Navigate  to the vCD public address page and see what is defined under the API address:

    • The ZVM attempts to connect to this address. While attempting to connect to the address, see if you are able to connect to the vCD API. Note that a "Connection Not Found" error can indicate a problem, but a "Format Cannot Be Displayed" error does not indicate a problem, since the API is accessible but cannot be displayed in Internet Explorer.

    • The address should not contain the word "api" at the end. If the address contains "api" at the end, remove it and try again.

  • Verify that IE proxy settings are disabled in the Internet Properties > LAN Settings section of the Windows Control Panel on the ZVM.

  • Failed Authentication at Site Settings --> Cloud Settings: verify username, password and server name. Also, please note that the Zerto Virtual Manager only supports TLS 1.0 and therefore it has to be enabled (Zerto currently doesn't support TLS 1.1 or 1.2). If TLS 1.0 is not enabled, authentication will fail as the SSL initiation is rejected by vCD).

When configuring the ZVM to receive notifications from vCD using the Zerto Virtual Replication AMQP installer, an exchange is created within the AMQP broker that matches the exchange listed for use within vCD's Blocking Tasks section ('VCD' by default). This information also exists in the VCD GUI under:
Administration->Extensibility->AMQP Broker Settings.
In addition, the installer attempts to bind the ZVM to a queue in the AMQP broker by default named 'ZertoVcdQueue-<guid>', where <guid> is the ZVM site identifier.  If this queue does not exist, the ZVM creates it and binds it to the vCD exchange so that messages posted to the exchange will be forwarded to the 'ZertoVcdQueue-<guid>' queue.  The ZVM then pulls messages from this queue.

 

If the connection to the vCD is working well but you receive an error regarding connectivity to AMQP, follow these steps:

 

  • The error message that is displayed in the ZVR GUI will usually state the source of the connection problem. For example:

    1. Connected to vcloud=Zerto.vCloud.com but failed to connect to AMQP-server for notifications (last connection error: "The AMQP operation was interrupted: AMQP close-reason, initiated by Peer, code=404, text="NOT_FOUND - no exchange 'systemExchange' in vhost '/'", classId=40, methodId=10, cause=").

      • This error message states that the connection to the vCD is OK but the issue is the connection to the AMQP. In this case, the error message states that the exchange called "systemExchange", that exist inside the AMQP by default, was deleted. In this case you will need to connect to the AMQP and recreate an exchange with the name "systemExchange". Connectivity checks (ping, telnet on relevant) should be considered at this point.

      • Note that the name of the exchange can be different and it depends on the settings that exist inside the vCD. If you receive the same error with the exchange set to "vCD" in vCD, then you will need to create an exchange with the name "vCD" within AMQP. In order to do that, you will need to enable the RabbitMQ GUI, as seen in this KB: https://www.zerto.com/myzerto/knowledge-base/install-rabbitmq-gui/

        • When creating the exchange, use the following parameters:

          • Type = fanout

          • Durable = true.

          • Everything else should be false.

  • Verify that the connection between vCD and the AMQP server is available.  

    1. To do so, log into vCD,. and navigate to Administration >  Extensibility.

    2. Click on "Test AMQP Connection".  Note that this option checks only for ping from vCD to the AMQP and credentials for connection to AMQP. This option does not check anything beyond ping and credentials.

    3. Should this test not be successful, check for the cause of the connection problem, such as:

      • Incorrect user and password

      • AMQP VM is down

      • Lack of route

      • Closed ports

 

If these troubleshooting steps do not help to determine the cause of the disconnect, or you do not understand the meaning of the alerts that appear in the ZVR GUI, contact Zerto Support.


Affected Versions:
3.5, 4.0, 4.5

Hypervisor:
VMware

1 Star2 Stars3 Stars4 Stars5 Stars (1 votes, average: 1.00 out of 5)
Loading...