Recently I upgraded my vCenter 6.7 U3 to vCenter 7.0 U1. During this upgrade, my Auto Deploy configuration was not adopted correctly.

After the vCenter upgrade, the iPXE Boot URL was incorrect. It pointed to the IP of the VCHA (vCenter High Availability) Nic and those IP was not available from the ESXi Subnet.

To fix this issue, you have to connect to your vCenter via SSH and fill the correct IP between the <serviceAddress> </serviceAddress> in the file /etc/vmware-rbd/autodeploy-setup.xml.

Using username "root".

VMware vCenter Server 7.0.1.00300

Type: vCenter Server with an embedded Platform Services Controller

Connected to service

    * List APIs: "help api list"
    * List Plugins: "help pi list"
    * Launch BASH: "shell"

Command> shell
Shell access is granted to root
root@vcsa01 [ ~ ]# cat /etc/vmware-rbd/autodeploy-setup.xml
<Config>
        <serviceAddress>MYvCenterIP</serviceAddress>

        <defaultValues>
            <port>6501</port>
            <portAdd>6502</portAdd>
            <maxSize>2</maxSize>
        </defaultValues>
        <vCenterServer>
            <address>MyvCenterFQDN</address>
            <port>80</port>
            <user>root</user>
        </vCenterServer>


        <debug>
            <level>INFO</level>
        </debug>
    </Config>root@vcsa01 [ ~ ]#

Now you have to restart the Auto Deploy Service or the complete vCenter.