I patched initrd :

diff usr/lib/dracut/hooks/initqueue/online/11-fetch-kickstart-net.sh usr/lib/dracut/hooks/initqueue/online/11-fetch-kickstart-net.sh.ORG
47d46
<           new_ip_address=${new_ip_address:-$(ip addr show $netif | awk '/inet / {split($2,ip,"/"); print ip[1];}')}

There is probably cleaner and I don't know if it covers all cases but for us it works :

INFO dracut-initqueue:anaconda: successfully fetched kickstart from nfs:srv:/linux/config/10.0.11.150-kickstart

Hello
I also have the same exact issue with F31.
Have also tried rawhide which has the same problem.
Thanks.

I have created a pull request that should fix the problem for future releases:
https://github.com/rhinstaller/anaconda/pull/2257

To fix the problem for Fedora 31, I think that users (administrators) must modify the file initrd.img manually, because Fedora doesn't release updates to installation media...

I didn't find a complete description how to patch initrd for current Fedora versions, only older (outdated?) hints. So this is the method that works for me. There may be better methods.

- I use image Fedora-Everything-netinst-x86_64-31-1.9.iso because I only need to boot using pxe over network. You can also use the server netinst or dvd iso image.

- Extract (copy) the content of the iso image to a directory. You can use command like "mount -o loop,ro path-to-iso-image path-to-mount" which must be done as root, or 

- For network installation with pxe, we need files in subdirectory os/images/pxeboot/: files vmlinuz and initrd.img .

- With "lsinitrd path-to-initrd.img" you can list the content of the file. "lsinitrd" is provided by package dracut.

- Create a new, empty directory for extracting the content of initrd.img, for example /tmp/initrd-content .
  Extract (copy) the content of initrd.img to this directory. You need to be root, because the file contains special files (char devices in dev/ ).

  # cd /tmp/initrd-content
  # lsinitrd --unpack path-to-initrd.img

- Store the patch in a file, for example /tmp/anaconda-kickstart-nfs-calculate-ip.patch

- Patch file dracut/fetch-kickstart-net.sh:

  # patch -p1 < /tmp/anaconda-kickstart-nfs-calculate-ip.patch

- Create a new file initrd.img. This is not perfect, because the size of the original and the new files differ too much, but it works for me.

  # (cd /tmp/initrd-content; find . -print0 | cpio -c -o --null | xz --check=crc32 --lzma2=dict=1MiB > /tmp/initrd.img-new )

- Use the new initrd.img file instead of the original (use /tmp/initrd.img-new, but with name initrd.img) in the usual places (tftp server, nfs server, direct boot, ...).

Created attachment 1649324 [details]
Patch file for comment #4

(In reply to Edgar Hoch from comment #3)
> I have created a pull request that should fix the problem for future
> releases:
> https://github.com/rhinstaller/anaconda/pull/2257

I have replaced the pull request by a new one:
https://github.com/rhinstaller/anaconda/pull/2258

Thank you for the patch, I am going to look at it soon.

As for the initrd update (comment #4), for PXE installations it should be also possible to use initrd overlay containing just fetch-kickstart-net.sh file (in its respective path) and then use something like this pxe configuration (with initrd.overlay.img overlay image):

label development-rawhide
  menu label development-rawhide
  kernel test/rv/scripted/development-rawhide/vmlinuz
  append initrd=test/rv/scripted/development-rawhide/initrd.img,test/rv/initrd.overlay.img repo=http://download.englab.brq.redhat.com/pub/fedora/development-rawhide/Everything/x86_64/os   ks=http://10.43.136.2/ks/rv/ks.network-service.cfg

Resolved in Fedora 32 Rawhide 20200112.n.0 nightly compose

I have used Fedora 32 Rawhide 20200112.n.0 nightly compose for a kickstart installation. Now the kickstart file is found, the problem descibed in this bug report is solved in this version.

Thanks Radek!

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Apparently some kind of fix has been included, see comment 8, and the EOL message is only because the bug was forgotten.