virtualbox-iso: Timeout waiting for SSH

User_SMLA4

I try to build OCI of oracle linux 8 by a physical linux machine (Centos7) and I followed the steps descriped in https://blogs.oracle.com/linux/building-small-oracle-linux-images-for-the-cloud. But failed with “virtualbox-iso: Timeout waiting for SSH” and I try more methods to fix it but failed so I need help about this,could anybody help me about the error?

The linux version of my physical linux machine is "Linux 3.10.0-123.el7.x86_64".

The version of packer is Packer v1.7.1.

The version VirtualBox is VirtualBox-6.1-6.1.20_143896_el7-1.x86_64.

The openssh is installed on my linux,the detail info is :

openssh-clients-6.4p1-8.el7.x86_64

openssh-server-6.4p1-8.el7.x86_64

openssh-6.4p1-8.el7.x86_64

The OL7U8_x86_64-none-b0.json file is

OL7U8_x86_64-none-b0.txt

Which I had to renmae it to txt extent format.

I'm not sure why it connnected to the SSH of localhost but the ssh service already be installed on my linux.How could it be hunged for waiting the ssh and finally it failed as timeout.

All I want to do is to build a customize oracle linux ISO by packer and Virtualbox.If anybody can help me it would be very kind of you,thanks a lot.