Adding a permanent static route in Solaris

Updated   Read time 1 min 23 sec(s)   (926 views).  Solaris  

You can use the route command to manually manipulate the network routing tables. Its primary use is to set up static routes to specific hosts or networks via an interface after it has been configured with the ifconfig(8) utility.

Note: The route command manipulates routes for the active system only. If you reboot the server the dynamic route will be lost. To prevent this from happening we can simply create a startup script in /etc/rc2.d directory.

Manually adding a route

Adding a route on the fly, we can issue the following:

route add [net|host] netmask [gateway|-interface]

Example #1

# route add -net 10.1.1.0 netmask 255.255.255.0 10.1.1.1

Example #2

# route add -net 10.1.1.0/24 10.1.1.1

Using the netstat command we can display the current routing table:

# netstat -nr
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.1.1.0        0.0.0.0         255.255.255.0   U     0      0        0 bge0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo

Setting the Default Route

Adding a default route using the route command with the gw sub-option. For example

# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.1.1.0        0.0.0.0         255.255.255.0   U     0      0        0 bge0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
# route add default gw 10.1.1.1
# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.1.1.0        0.0.0.0         255.255.255.0   U     0      0        0 bge0
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         10.1.1.1        0.0.0.0         UG    0      0        0 bge0

To make route entries persistant across reboots we need to add the entries into a startup script. For example:

# vi /etc/rc2.d/S99static-routes
#!/sbin/sh
#
# Add static routes
#
route add net 10.1.1.0 netmask 255.255.255.0 10.1.1.1 1
route add net 192.168.1.0 netmask 255.0.0.0 10.2.1.1
# chown root:root /etc/rc2.d/S99static-routes
# chmod 0744 /etc/rc2.d/S99static-routes

To create a persistent defailt route across system reboots, add the hostname or IP address of the default routers into the file /etc/defaultrouter. For example:

# vi /etc/defaultrouter
10.1.1.1