For the last few weeks, whenever my pppoe connection was restarted, I have had to disable the defaultroute option on the connection, and re-enable the option (presumably this simply reinstalls the default route) before packets are routed properly (otherwise pings from the router simply times out). I have checked the routing table, and the default route is correctly configured the first time, so I'm not sure why the above was necessary. Here is my network config:
config interface 'loopback'
option ifname 'lo'
option proto 'static'
option ipaddr '127.0.0.1'
option netmask '255.0.0.0'
config interface 'lan'
option type 'bridge'
option proto 'static'
option netmask '255.255.255.0'
option ipaddr '10.97.2.1'
option _orig_ifname 'eth0.1 wlan0 wlan1'
option _orig_bridge 'true'
option ip6assign '64'
option ifname 'eth0.1'
option metric '0'
config switch
option reset '1'
option enable_vlan '1'
option max_length '3'
option enable_vlan4k '1'
option name 'switch0'
config switch_vlan
option vlan '1'
option ports '0 1 2 3 5t'
option device 'switch0'
config interface 'modem'
option proto 'static'
option ifname 'eth1'
option ipaddr '192.168.1.2'
option netmask '255.255.255.0'
option metric '0'
config interface 'vpn'
option proto 'none'
option ifname 'vpns+'
config interface 'wan'
option proto 'pppoe'
option password '...'
option ipv6 'auto'
option username '...'
option peerdns '0'
option keepalive '2 5'
option ifname 'eth1'