I am using a SuperMicro server, and its ipmi firmware has a so called "Virtual Media" function. It allows you to mount an iso file, which is then presented to server as a usb cdrom.
I cannot understand why some of the iso files are not mountable. When I choose an iso file in Virtual Storage menu, and then click Plug in button, I got message:
Device1: Can not open ISO Image File
But some other iso files are able to be mounted correctly with the message:
Device1: VM Plug-In OK!!
I thought that the iso file size could be a problem, but seems it is not.
Edit: there is a similar question, but in that case the cause was firewall.