diff --git a/install.py b/install.py
index d723de2..7eca789 100755
--- a/install.py
+++ b/install.py
@@ -15,6 +15,7 @@ import filecmp
 import re
 import types
 import socket
+import tempfile
 from pathlib import Path
 from subprocess import Popen, PIPE
 from ipaddress import IPv4Interface
@@ -520,9 +521,9 @@ def handle_config():
                 box.typ = 'bare-apu'
         elif box.typ == 'cm4':
             box.typ = 'dual-eth-rpi'
-            print('This is a cm4, so guess its a dual-eth-rpi - please check type in cfg file')
+            print('This is a cm4, so guess its a dual-eth-rpi - please check type in created cfg file')
         elif box.typ == 'cm3':
-            print('This is a cm3 so guess its a ionopimax  - please check type in cfg file')
+            print('This is a cm3 so guess its a ionopimax  - please check type in created cfg file')
             box.typ = 'ionopimax'
         template = TEMPLATES.get(box.typ)
         if template is None:
@@ -542,10 +543,9 @@ def handle_config():
         config = box.read_config()
         cfgfile = box.cfgfile
     if box.hostname_changed or box.hostname != newhostname:
-        print('changed', box.hostname, newhostname)
         box.hostname_changed = True
         if cfgfile:
-            newhostname = cfgfile.stem.rpartition('_')[0]
+            newhostname = cfgfile.stem.split('_')[0]
         if doit:
             print('bash sethostname.sh')
             unix_cmd('bash', f'{TOOLS}/sethostname.sh')
@@ -561,48 +561,49 @@ def handle_config():
     ifname = ''
     try:
         netcfg = config.get('NETWORK', {})
-        for name in netcfg:
-            if name not in box.network_interfaces:
-                print(f'{name} is not a valid network interface name')
-                raise RuntimeError('network interface name system does not match')
-        for ifname in box.network_interfaces:
-            content = create_if(ifname, netcfg.get(ifname, 'off'))
-            # content = '\n'.join('%s=%s' % kv for kv in content.items())
-            todo = write_when_new(f'/etc/network/interfaces.d/{ifname}', content, as_root=True)
-            if todo and not more_info:
-                print('change', ifname)
-                show.dirty = True
-                to_start[ifname] = 'if_restart'
-        if dhcp_server_cfg:
-            content = [DHCP_HEADER]
-            for subnet, rangelist in dhcp_server_cfg:
+        if netcfg:  # when not network is specified, do not handle network at all
+            for name in netcfg:
+                if name not in box.network_interfaces:
+                    print(f'{name} is not a valid network interface name')
+                    raise RuntimeError('network interface name system does not match')
+            for ifname in box.network_interfaces:
+                content = create_if(ifname, netcfg.get(ifname, 'off'))
+                # content = '\n'.join('%s=%s' % kv for kv in content.items())
+                todo = write_when_new(f'/etc/network/interfaces.d/{ifname}', content, as_root=True)
+                if todo and not more_info:
+                    print('change', ifname)
+                    show.dirty = True
+                    to_start[ifname] = 'if_restart'
+            if dhcp_server_cfg:
+                content = [DHCP_HEADER]
+                for subnet, rangelist in dhcp_server_cfg:
+                    try:
+                        adr, mask = subnet.split('/')
+                    except Exception as e:
+                        print(subnet, repr(e))
+                        continue
+                    content.append('subnet %s netmask %s {\n' % (adr, mask))
+                    #content.append('    option netmask %s;\n' % mask)
+                    for rng in rangelist:
+                        content.append('    range %s %s;\n' % rng)
+                    content.append('}\n')
+                content = ''.join(content)
+                todo = write_when_new('/etc/dhcp/dhcpd.conf', content, as_root=True)
+                if todo:
+                    print('change dhcpd.conf')
+                    to_start['isc-dhcp-server'] = 'restart'
+                    show.dirty = True
                 try:
-                    adr, mask = subnet.split('/')
-                except Exception as e:
-                    print(subnet, repr(e))
-                    continue
-                content.append('subnet %s netmask %s {\n' % (adr, mask))
-                #content.append('    option netmask %s;\n' % mask)
-                for rng in rangelist:
-                    content.append('    range %s %s;\n' % rng)
-                content.append('}\n')
-            content = ''.join(content)
-            todo = write_when_new('/etc/dhcp/dhcpd.conf', content, as_root=True)
-            if todo:
-                print('change dhcpd.conf')
-                to_start['isc-dhcp-server'] = 'restart'
-                show.dirty = True
-            try:
-                replace_in_file('/etc/default/isc-dhcp-server',
-                                r'INTERFACESv4="(.*)"', ' '.join(
-                                [n for n in box.network_interfaces if n != box.main_if]))
-            except FileNotFoundError:
-                if 'yes'.startswith(input('install isc-dhcp-server? [y]')):
-                    unix_cmd('apt-get install isc-dhcp-server')
-                exit()
-        elif doit:
-            unix_cmd('systemctl stop isc-dhcp-server')
-            unix_cmd('systemctl disable isc-dhcp-server')
+                    replace_in_file('/etc/default/isc-dhcp-server',
+                                    r'INTERFACESv4="(.*)"', ' '.join(
+                                    [n for n in box.network_interfaces if n != box.main_if]))
+                except FileNotFoundError:
+                    if 'yes'.startswith(input('install isc-dhcp-server? [y]')):
+                        unix_cmd('apt-get install isc-dhcp-server')
+                    exit()
+            elif doit:
+                unix_cmd('systemctl stop isc-dhcp-server')
+                unix_cmd('systemctl disable isc-dhcp-server')
         displaycfg = config.get('DISPLAY')
         if displaycfg and display_update(displaycfg):
              to_start['display'] = 'restart'
diff --git a/utils.py b/utils.py
index 4828f13..824640b 100644
--- a/utils.py
+++ b/utils.py
@@ -115,7 +115,7 @@ class BoxInfo:
                         break
         if not cfgfiles:
             cfgfiles = list(self.CFGDIR.glob(f'*_{self.id:06x}.cfg*'))
-            self.oldcfg = True
+            self.oldcfg = bool(cfgfiles)
         if len(cfgfiles) > 1:
             raise AmbiguousConfigFile('ambiguous cfgfile: %r' % cfgfiles)
         if section and not cfgfiles: