rtems_bsdnet_show_inet_routes

[Ian Caddy]

Hi Leon,

I have had to explain almost the same things previously to our 
customers, so I have researched this in the past.

Leon Pollak wrote:
> I have the board with two interfaces. When I run rtems_bsdnet_show_inet_routes 
> with both interfaces configured with static IP addresses I receive the 
> following:
> --
> Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
> 127.0.0.1       127.0.0.1          UH          0        0      0 lo0
> 192.168.1.0     255.255.255.0      U           0        0      2 eth1
> 192.168.50.0    255.255.255.0      U           0        0      1 eth0
> --
> But, when I define the first IF "eth0" to use bootp protocol, the result looks 
> as following:
> 
> Destination     Gateway/Mask/Hw    Flags     Refs     Use Expire Interface
> default         192.168.50.1       UGS         0        0      0 eth0
> 127.0.0.1       127.0.0.1          UH          0        0      0 lo0
> 192.168.1.0     255.255.255.0      U           0        0      2 eth1
> 192.168.50.0    255.255.255.0      U           0        0      4 eth0
> 192.168.50.1                       UHL         1        0      4 eth0
> 
> -----------------
> The questions are:
> 1. What do the last 2 lines mean?

The first of the two last lines is for the default route for the subnet 
of eth0, the same as the last line in the first section.

The last line is for the the connection you have had with that 
particular IP address (your DHCP server).

This table is your current routing table.

> 2. What is the "Expire" column meaning?

The expire column indicates that the particular route will be dropped if 
there is no activity for the expiry time.

> 3. How are the "Flags" column letters interpreted?

Since the stack comes from BSD, I have a link that explains a lot of 
what I am telling you as well:

http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-routing.html

Here is the list of flags:

U	Up: The route is active.
H	Host: The route destination is a single host.
G	Gateway: Send anything for this destination on to this remote
	system, which will figure out from there where to send it.
S	Static: This route was configured manually, not automatically
	generated by the system.
C	Clone: Generates a new route based upon this route for machines
	we connect to. This type of route is normally used for local
	networks.
W	WasCloned: Indicated a route that was auto-configured based upon
	a local area network (Clone) route.
L	Link: Route involves references to Ethernet hardware.


Hope this helps.

regards,

Ian Caddy

-- 
Ian Caddy
Goanna Technologies Pty Ltd
+61 8 9444 2634