Debian-Server verliert Netzwerk-Konfiguration nach Neustart

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug eth0
iface eth0 inet static
        address 193.26.X.X
        netmask 255.255.255.248
        network 193.26.X.X
        broadcast 193.26.X.X
        gateway 193.26.X.X
        # dns-* options are implemented by the resolvconf package, if installed
        dns-nameservers 193.26.X.X
        dns-search XXXXXXX.com

#!/bin/sh -e
### BEGIN INIT INFO
# Provides:          networking
# Required-Start:    mountkernfs ifupdown $local_fs
# Required-Stop:     ifupdown $local_fs
# Default-Start:     S
# Default-Stop:      0 6
# Short-Description: Raise network interfaces.
### END INIT INFO

PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin"  

[ -x /sbin/ifup ] || exit 0

. /lib/lsb/init-functions

process_options() {
    [ -e /etc/network/options ] || return 0
    log_warning_msg "/etc/network/options still exists and it will be IGNORED! Read README.Debian of netbase."  
}

check_network_file_systems() {
    [ -e /proc/mounts ] || return 0

    exec 9<&0 < /proc/mounts
    while read DEV MTPT FSTYPE REST; do
        case $DEV in
        /dev/nbd*|/dev/nd[a-z]*|/dev/etherd/e*)
            log_warning_msg "not deconfiguring network interfaces: network devices still mounted."  
            exit 0
            ;;
        esac
        case $FSTYPE in
        nfs|nfs4|smbfs|ncp|ncpfs|cifs|coda|ocfs2|gfs|pvfs|pvfs2|fuse.httpfs|fuse.curlftpfs)
            log_warning_msg "not deconfiguring network interfaces: network file systems still mounted."  
            exit 0
            ;;
        esac
    done
    exec 0<&9 9<&-
}

case "$1" in  
start)
        process_options

        log_action_begin_msg "Configuring network interfaces"  
        if ifup -a; then
            log_action_end_msg $?
        else
            log_action_end_msg $?
        fi
        ;;

stop)
        check_network_file_systems

        log_action_begin_msg "Deconfiguring network interfaces"  
        if ifdown -a --exclude=lo; then
            log_action_end_msg $?
        else
            log_action_end_msg $?
        fi
        ;;

force-reload|restart)
        process_options

serv:/etc/udev/rules.d# ls -al /sys/class/net
insgesamt 0
drwxr-xr-x  4 root root 0  3. Aug 00:19 .
drwxr-xr-x 29 root root 0  3. Aug 00:19 ..
drwxr-xr-x  4 root root 0  3. Aug 00:19 eth0
drwxr-xr-x  4 root root 0  3. Aug 00:19 lo