[CentOS] network interface question

Hi,

I don't have ifcfg-eth1 in my /etc/sysconfig/network-scripts. But when I do ifconfig eth1 I can see output as below. If I do ifconfig eth12 , I don't see anything which i am assume is normal.

eth1 Link encap:Ethernet HWaddr 00:24:E8:44:DB:CC BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Interrupt:17 Memory:e8000000-e8012800

Don't know why and how this is happening.

Thanks! Paras.