Based on the error message:
Root-NFS: Server returned error -13 while mounting /tftpboot/ltib/rootfs
I'd make sure your server is exporting /tftpboot/ltib/rootfs.
Does your /etc/exports file have a line similar to:
/tftpboot/ltib/rootfs *(rw,no_root_squash,no_subtree_check,async)After doing that did you restart the NFS server to reread the exports? I do the following:
sudo /etc/init.d/nfsserver restart
Does any of that help?
--Kurt