Re: In network bonding second nic (eth1) is not pingable while first one (eth0) is always pingable"
On 8/22/20, Dan Ritter <dsr@randomstring.org> wrote:
> Jaikumar Sharma wrote:
>> On Fri, Aug 21, 2020 at 9:30 PM Dan Ritter <dsr@randomstring.org> wrote:
>> > You don't want a bond, you want a bridge.
>> >
>> > Bonding takes two interfaces that talk to the same switch on the
>> > other side, and makes them into one bond nic. You need support
>> > on the switch, too, which is unlikely in a D-Link 8-port unless
>> > it has a management interface -- I think they don't bother under
>> > 16 or 24 ports, and even then it's an extra-cost option.
>> Just see this webpage on
>> https://access.redhat.com/documentation/en-us/red_hat_openstack_platform/13/html/advanced_overcloud_customization/overcloud-network-interface-bonding
>> it says :
>>
>> bond_mode=active-backup
>>
>> This mode offers active/standby failover where the standby NIC resumes
>> network operations when the active connection fails. Only one MAC
>> address is presented to the physical switch. This mode does not
>> require any special switch support or configuration,and works when the
>> links are connected to separate switches. This mode does not provide
>> load balancing.
>>
>> ** This mode does not require any special switch support or
>> configuration -- stated in the above para.
>> Now, with this is not really clear where the problem is?
>
> You still want bridging, not bonding.
>
> WiFi doesn't have a cable, so it can't tell you when the
> connection goes away, and it can't decide by itself to bring up
> a connection. You need a management program that will pick a
> network from SSID, negotiate any necessary encryption, and do
> all that with a MAC address that does not conflict with another
> one on the network.
>
> The bond driver itself can't do that. You might be able to get a
> higher-order system to take care of it --
> /etc/network/interfaces *may* be able to figure out a way,
> Network Manager might handle this case -- but I'll bet you a
> shiny nickel you will have reliability issues that are much
> worse than just connecting it to the wired ethernet and leaving
> it alone.
Or you can just configure the wired ethernet connection to have a
lower (better) routing metric than the wireless connection. That way
the machine always uses the wired connection if it's up and uses the
wireless connection when the wired connection is down.
There's probably a nice and easy way to do that by changing
/etc/network/something .. I never figured out how to do it that way &
used the 'Advanced Network Configuration' gui tool to set the wired
connection 'Connect automatically with priority' to -999
With the ethernet cable connected to the laptop, 'ip route' shows wls1
with a metric of 600 and enp1s0 with a metric of 100.
With the ethernet cable disconnected the only thing that 'ip route'
shows is wls1.
Yay! automatic failover + automatic selection of the faster interface
when it's up :-)
Lee
Reply to: