Hi, I'm having trouble configuring network access and I hope you can help.
I recently reinstalled Red Hat Enterprise 6.3 and set up the NetworkManager to configure my dhcp connection to a wired network.
I also altered the ifcfg-eth0 file to include the lines ONBOOT="yes" and BOOTPROTO="dhcp".
I'm not sure if this was the right thing to do, but in any case it worked, and I had full connectivity. Today, I had to reboot the computer and when I did I could no longer connect to the network; NetworkManager doesn't seem to be able to acquire an IP address.
I've tried multiple options to fix this problem, using the NetworkManager and network services. I've tried every possible combination of the ifcfg-eth0 and /etc/sysconfig/network files, including or removing HWADDR, GATEWAY and NM_CONTROLLED parameters.
Basically, when I try to connect via NetworkManager I just get a message saying either 'The network was disconnected' or 'Device not managed', depending on the options I included. When I try to connect via the network service (i.e. 'service network restart') the startup hangs on the line 'Determining IP information for eth0...', regardless of what options I have used.
I don't think there are any hardware problems as I managed to connect before (apparently by pure fluke) and I know the network port is active.
I'd really appreciate any advice you can offer here; I'm sure I've just done something stupid or missed an obvious clue, but I'm not sure what to do next.
Output of ifconfig:
eth0 Link encap:Ethernet HWaddr 18:03:73:3F:FD:AB
inet6 addr: 2002:8fef:aabb:4:1a03:73ff:fe3f:fdab/64 Scope:Global
inet6 addr: fec0::4:1a03:73ff:fe3f:fdab/64 Scope:Site
inet6 addr: fe80::1a03:73ff:fe3f:fdab/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1792490 errors:1 dropped:0 overruns:0 frame:1
TX packets:834 errors:0 dropped:0 overruns:0 carrier:0
RX bytes:189774068 (180.9 MiB) TX bytes:241652 (235.9 KiB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:30 errors:0 dropped:0 overruns:0 frame:0
TX packets:30 errors:0 dropped:0 overruns:0 carrier:0