Issue with forwarding when creates new interface [was USB Tethering and forwarding]

[John Baldwin]

On 1/3/15 1:06 PM, Mike Tancsa wrote:
> On 1/3/2015 9:19 AM, Paul Thornton wrote:
>> Hi,
>>
>> I can also replicate this behaviour on 10.1-RELEASE by simply creating
>> an additional vlan interface.  It affects IPv4 and IPv6 forwarding.
> 
> Strange, I dont see that on RELENG_10
> 
> 0{marble}# ifconfig em2 up
> 0{marble}# ifconfig em2.3 create 1.1.1.2/24
> 0{marble}# sysctl -a | grep forwarding
> net.inet.ip.forwarding: 1
> net.inet.ip.fastforwarding: 0
> net.inet6.ip6.forwarding: 0
> 0{marble}# ifconfig vlan4 create 2.2.2.2 vlan 4 vlandev em2
> 0{marble}# sysctl -a | grep forwarding
> net.inet.ip.forwarding: 1
> net.inet.ip.fastforwarding: 0
> net.inet6.ip6.forwarding: 0
> 0{marble}#
> 
> do you set forwarding via just /etc/sysctl.conf or in /etc/rc.conf via
> ipv6_gateway_enable and gateway_enable. I seem to recall some discussion
> about there being a difference.  Perhaps devd is calling something that
> then fiddles with the setting ignoring whats in sysctl.conf ?

Yes, devd is running /etc/rc.d/netif start <foo> which probably checks
gateway_enable and sets the sysctl based on that overriding what it in
sysctl.conf.  Just set gateway_enable=YES in rc.conf instead.

-- 
John Baldwin