[CentOS] additional network config

Sun Jan 4 18:32:32 UTC 2015
ken <gebser at mousecar.com>

A system whose network routing table looks like this (abbreviated):

Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
0.0.0.0         192.168.0.1     0.0.0.0         UG    0      0        0 eth0

needs to look like this:

Destination     Gateway         Genmask         Flags Metric Ref    Use 
Iface
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
10.10.0.0       192.168.0.98    255.255.0.0     UG    0      0        0 eth0
0.0.0.0         192.168.0.1     0.0.0.0         UG    0      0        0 eth0

The first table is nicely configured by the files under /etc/sysconfig/.

The first table becomes the second when this command is run:

route add -net 10.10.0.0/16 gw 192.168.0.98 eth0

The question is, which file(s) need to be configured under 
/etc/sysconfig/-- and with what-- in order to accomplish what the "route 
add ..." command does?