Default Gateway for a system v/s Default gateway per Interface

[Alexander Amelkin]

Please, Ratan, if you implement those per-interface gateways again, 
could you leave an option to have a single system-wide default gateway 
only?

I honestly don't see any use for multiple gateways without policy 
routing being implemented, and then I don't see any use for policy 
routing in a BMC (as opposed to a router). So I would like to keep us 
from unneeded questions from the customers, and so I would prefer to 
have only a single gateway, as well as single sets of DNS and NTP 
servers without having to patch across the whole OpenBMC codebase.

If there was a compile-time option (distro/machine feature?) to use 
either per-interface or system-wide gateway/DNS/NTP, that would be very 
nice.

Thank you.
Alexander.

P.S. Sorry for sending this twice, forgot to include the list the first 
time.

24.04.2020 18:06, Ratan Gupta пишет:
> Hi All,
>
> Currently, OpenBMC stack allows a single default gateway for the 
> system. Latest kernel allows to configure multiple default gateways.
>
> Eg: In a system with two interfaces eth0 and eth1,
>
> eth0 configured with static address and having gateway(192.168.2.1)
> eth1 configured with DHCP and gets Gateway from DHCP server (10.10.10.1)
> ~~~~~~~~~~~~~
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  
> irtt Iface
> 0.0.0.0         19.168.2.1      0.0.0.0         UG        0 0          
> 0 eth0
> 0.0.0.0         10.10.10.1      0.0.0.0         UG        0 0          
> 0 eth1
> ~~~~~~~~~~~~~~
>
> Kernel will first try using the default gateway having higher metric 
> value and then fall back to the lower.
>
> More references: 
> https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/networking_guide/sec-configuring_the_default_gateway
>
> I'm proposing to make this change in the openBMC D-bus interfaces to 
> tie the gateway property with the Ethernet interface schema instead of 
> System configuration.
>
> Ethernet Interface Schema =>
>
> https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/xyz/openbmc_project/Network/EthernetInterface.interface.yaml 
>
>
> System Configuration Schema =>
>
> https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/xyz/openbmc_project/Network/SystemConfiguration.interface.yaml 
>
>
>
> Please let me know your suggestions.
>
> Regards
> Ratan Gupta
>