B3 WiFi ping anomaly

[jmilton]

Hi,

Got a weird one with my B3, which is my WiFi access point.

I have a Fujitsu scansnap 500 on my WiFi network which works with my android phone over WiFi. All good except the scanner occasionally disappears.

I have debugged this as a router problem.

From the router/B3 I can always ping the scanner.

From a laptop I can always ping the scanner if using a wired connection to the B3.

If the same laptop is WiFi connected the ping to the scanner returns destination unreachable.

The laptoo can always ping the B3 successfully.

I have tried adding an ACCEPT rule for ping to the start of the forward chain in the filter table but no improvement.

I can't figure out how the B3 maps both the lan and WiFi to BR0. Might be useful knowing that.

Any help appreciated

Thanks

[jmilton]

Some more info

All other network functions work.
SSH
Samba
Internet

Here's the weird bit

If I reboot the B3 the problem goes away but will return at some point.

Thanks

[Gordon]

Sounds like a DNS/DHCP issue. You should probably check and monitor your dnsmasq.leases file. A possible fix could be to assign the scanner a fixed IP and network name in your DHCP configuration.

[jmilton]

Hi Gordon,

Thanks for your thoughts on this.

I have been thinking the same and waited for the scanner's DHCP lease to expire but when it did it renewed successfully and the scanner continued to work. I have not looked at the leases file you suggest however and will do so next time I lose connection.

Last time the connect went down coincided with a log file rotation. I'm suspicious that the rotation has caused something important to crash.

Thanks again!