ifcfg-em1 ?

[Jeffrey Ross]

I was in the process of working on a F16 system (upgraded from a F15 
system) and had moved it to a new network temporarily and had adjusted 
the /etc/sysconfig/network-scripts/ifcfg-em1 file from the console prior 
to shutting down the system so that it would be all set with the new 
address, gateway etc when it was restarted.

upon completion of the work I modified the ifcfg-em1 with the new/final 
IP address information prior to the shutdown.  I was doing this across a 
network (ssh) session and as soon as I saved the file I lost all 
connectivity to the machine.  I logged into the console and found no IP 
address information on the em1 interface, didn't think too much of it 
since it needed to be restarted anyway and moved it to it final network 
location.

After it was in place I noticed that I needed to correct the entries for 
DNS to point to itself since it is running a nameserver, no other 
changes were made to the file except to adjust "DNS1=..." saved the file 
and again I loose network connectivity with no IP information on the em1 
interface.

Question is, what is monitoring this file that causes a loss of 
connectivity like this?  I am looking to simply have a static entry on 
the interface and my simple ifcfg-em1 file is as follows:

Thanks,Jeff

DEVICE=em1
HWADDR=00:E0:81:34:85:C2
NM_CONTROLLED=no
ONBOOT=yes
TYPE=Ethernet
USERCTL=no
#
BOOTPROTO=none
NETMASK=255.255.255.240
IPADDR=192.168.10.34
PREFIX=28
DOMAIN=domain.org
NAME="System em1"
IPV6INIT=yes
NM_CONTROLLED=no
GATEWAY=192.168.10.33
DNS1=192.168.10.34
MTU=1500
PEERDNS=yes