On powerpc DNS resolution does not always work:

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IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM IBM 
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                             GNU GRUB  version 2.02

   Minimal BASH-like line editing is supported. For the first word, TAB   

                             GNU GRUB  version 2.02

   Minimal BASH-like line editing is supported. For the first word, TAB   
   lists possible command completions. Anywhere else TAB lists possible   
   device or file completions.                                            


grub> insmod http
grub> net_add_dns 10.160.0.1
grub> linux
(http,download.suse.de)/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DVD
1/boot/ppc64le/linux
install=http://download.suse.de/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DVD1
error: no DNS reply received.
grub> net_add_dns 10.160.0.100                                                 
grub> linux (http,download.suse.de)/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DV
D1/boot/ppc64le/linux
install=http://download.suse.de/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DVD1
error: no DNS reply received.
grub> linux (http,download.suse.de)/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DV
D1/boot/ppc64le/linux
install=http://download.suse.de/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DVD1
grub> initrd
(http,download.suse.de)/install/SLP/SLE-12-SP4-Server-GM/ppc64le/DVD1/boot/ppc64le/initrd
grub> boot


Is this known issue? How do I tell which exact grub version I have?