[CentOS] How to PXE kickstart hosts with little memory (Error: "Warning: /dev/root does not exist")?

[Frank Thommen]

On 04/21/2017 10:25 PM, Gordon Messmer wrote:
> On 04/21/2017 12:49 PM, Frank Thommen wrote:
>>
>> It seems, that this is not related to local disk space - as I initally
>> thought - but to too small memory.  It only happens with VMs with
>> little RAM (1024 MB).  As soon as we raise the available memory to
>> 2048 MB, kickstarting works fine.  The RHEL 7 installation guide
>> states, that the minimal memory requirement is 1 GB, so the network
>> installation /should/ work.
>
> Yeah, I filed a bug report against the documentation some time ago.
>
> https://bugzilla.redhat.com/show_bug.cgi?id=1410948
>
> ...though bugzilla is currently down.
>
>> Is there a way to install such hosts w/o having to temporarily raise
>> the available memory?
>
>
> None that I'm aware of, as of 7.3.  If you have a 7.2 install tree, you
> can boot the older installer and then update the installed system.
> Seems easier to boost the memory, typically.

I gave it a try with 7.2.1511 and that works fine as long as I have 
"ip=eth0:dhcp" in my PXE config.  As soon as I expand it to 
"ip=eth0:dhcp ip=eno1:dhcp rd.neednet=1" (I do that to make sure 
kickstart works independently from the name of the network interface), 
kickstart enters into emergency mode w/o any error message after a lot 
of timeout warnings.  However that's something we can work around.

Thanks for the 7.2 hint.

frank