Centos5.1xenvirt-manager displays Unable when creating a VM

Centos5.1xenvirt-manager displays Unable -- Linux Enterprise Application-Linux server application information when creating a VM. The following is a detailed description. Because building a test environment requires multiple servers, you need to use a dual-CPU server to virtualize multiple servers by using xen virtual machine technology.
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First install this server. The operating system is centos5.1. You must select "virtualization" during installation ".

Since my installation disk is a DVD, this server's optical drive is a CD-ROM and cannot be installed directly. Therefore, the network installation method is used. Burn a boot disk with a CD-ROM, and then install a lighttpd on your desktop, the drive on this machine is a DVD-ROM, connect/media/centos_5.20.final to/var/www/html/centos.

Then, start the server with the boot CD and install it in http mode.
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After centos5.1 is installed, you can configure and install the xen virtual machine. Since the server is in a small room, I want to install it remotely.

Use command: ssh-X root@192.168.100.225

Connect to the server and run the following command: virt-manager

Now you can configure a virtual machine.
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In the Locating installation media step, Install Media URL enters: http: // 192.168.100.220/centos

In the last step, the system reports "Unable to complete install: 'invalid install location '". This problem has been encountered before and cannot be solved. This time I finally found the cause. Because the configured lighttpd cannot list directories, the Error 404 returned when accessing http: // 192.168.100.220/centos is returned.

Add: dir-listing.activate = "enable" to the lighttpd configuration file"

This configuration allows lighttpdto list directories when index.htm is not found. Therefore, 200 is returned for access.
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The installation of the virtual machine went very smoothly this time.
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This problem is indeed very difficult, because I have successfully installed centos with the same source, but the same source won't work when installing virtual machines. It is estimated that virt-manager accesses this url to check whether the http source is normal, and the 404 error is returned because the directory cannot be listed, make virt-manager think this source is incorrect.