need help with ifconfig command line

[chipsafts]

here is the current output of ifconfig

eth1 Link encap:Ethernet HWaddr 00:C8:09:C3:0F:91
inet addr:10.15.35.79 Bcast:10.15.35.95 Mask:255.255.255.224
inet6 addr: fe70::2d5:9ff:fec3:f71/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:48825240 errors:0 dropped:0 overruns:0 frame:0
TX packets:29007556 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1717150188 (1.5 GiB) TX bytes:3147960533 (2.9 GiB)
Interrupt:11 Base address:0xd400

eth1:3 Link encap:Ethernet HWaddr 00:C8:09:C3:0F:91
inet addr:10.15.35.83 Bcast:10.15.35.95 Mask:255.255.255.224
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:11 Base address:0xd400

eth1:5 Link encap:Ethernet HWaddr 00:C8:09:C3:0F:91
inet addr:192.168.1.51 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:11 Base address:0xd400

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:20842 errors:0 dropped:0 overruns:0 frame:0
TX packets:20842 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:18520113 (17.6 MiB) TX bytes:18520113 (17.6 MiB)

How can I use ifconfig to "clone" the settings of eth1:5 to eth1:7 with an ip address of 192.168.1.5 ?

My real goal is to have this pc poll our main RedHat server's ip address and if no response (ie: RH is down), then this pc should take over the ip address of the RH and provide the email and internal DNS services.

[zcworld]

i can give u half a tip
for the DNS
on the server thats gives out the DHCP

just add
second DNS IP to
option domain-name-servers line

here mine
option domain-name-servers 192.168.1.10, 192.168.1254;


.10 = my inhouse DNS serer
.254 = router - DNS