dkms.conf is in /usr/src/r8168-8.035.00

dkms.conf

PACKAGE_NAME=r8168
PACKAGE_VERSION=8.035.00
MAKE[0]="'make' modules"
BUILT_MODULE_NAME[0]=r8168
BUILT_MODULE_LOCATION[0]="src"
DEST_MODULE_LOCATION[0]="/kernel/updates/dkms"
AUTOINSTALL="YES"

gistfile1.sh

# ls -l /lib/modules/2.6.32-17-pve/updates/dkms/r8168.ko 
-rw-r--r-- 1 root root 525K May 17 19:18 /lib/modules/2.6.32-17-pve/updates/dkms/r8168.ko
# ls -l /lib/modules/2.6.32-19-pve/updates/dkms/r8168.ko 
-rw-r--r-- 1 root root 525K May 17 19:19 /lib/modules/2.6.32-19-pve/updates/dkms/r8168.ko

# dkms status
r8168, 8.035.00, 2.6.32-17-pve, x86_64: installed 
r8168, 8.035.00, 2.6.32-19-pve, x86_64: installed

# lsinitramfs /boot/initrd.img-2.6.32-17-pve | grep r8168
lib/modules/2.6.32-17-pve/updates/dkms/r8168.ko
# lsinitramfs /boot/initrd.img-2.6.32-19-pve | grep r8168
lib/modules/2.6.32-19-pve/updates/dkms/r8168.ko

# cat /etc/modprobe.d/blacklist-network.conf 
blacklist r8169

# cat /etc/modules 
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
# Parameters can be specified after the module name.

loop
r8168