[CUWiN-Dev] multiple gateways?

[David Young]

On Mon, Dec 12, 2005 at 05:57:14PM -0600, Bill Comisky wrote:
> 
> In lawndale we put up a second gateway (stower) in the old Sears Tower on 
> the south side of the building facing south; our existing gateway (wtower) 
> there is on the west side facing NW.  These gateways are plugged into the 
> same LAN served by the same dhcp server, and as of now have the same SSID 
> and channel.
> 
> Though they face different directions (sector antennas) and have a fair 
> amount of building in between, their radios can hear each other.  There is 
> a small amount of overlap on the ground, where one or two nodes can hear 
> both gateways.  Will CUWiN "do the right thing" in this scenario, or would 
> it be better to make distinct networks with different channels and/or 
> SSIDs?
> 
> It seemed to work OK for a while, we started with revision 3658.  We were 
> having issues with hslsd core dumps and losing the default route.  In 
> light of the many recent fixes, I just upgraded the stower node to 
> revision 3715 on 8-Dec netbsd snapshot.  hslsd dropped core within a few 
> minutes, but has stayed up since I restarted it.  However the default 
> route seems wacky.  Instead of having a default route to the gateway given 
> by the dhcp server, its default route jumps around, alternately to:
> 
> 192.168.4.3     # the LAN address of wtower which is still running r3658
> 169.254.233.14  # standalone node that can see both gateways, which has
> 		# a default route to wtower

The directly-connected route will always take precedence, it will have
a better path metric.  Maybe you have a mixture of versions, such that
the default metric for "stub" routes is lower on some nodes than others?
Ah, yes, that is it:

svn diff -r3658:3715 hsls_metrics.c 
Index: hsls_metrics.c
===================================================================
--- hsls_metrics.c      (revision 3658)
+++ hsls_metrics.c      (revision 3715)
@@ -145,7 +145,6 @@ hsls_metric_default_val(enum hsls_metric
        case HSLS_METRIC_RADIUS:
                return 1;
        case HSLS_METRIC_ETX:
-               return ETX_UNIT;
        default:
                return HSLS_DOWN_METRIC;
        }

Dave

-- 
David Young             OJC Technologies
dyoung at ojctech.com      Urbana, IL * (217) 278-3933