Re: How to address 'ping -I <interface>' failure

[Grant Taylor <gtaylor@xxxxxxxxxxxxxxxxxx>]

On 01/22/2018 09:55 AM, Leroy Tennison wrote:
> I'm just beginning to learn about multiple routing tables so I tried the 
> following suspecting it wouldn't work (and it didn't): 'ip rule add from 
> eth1 table dsl' and got 'Error: ??? prefix is expected rather than "eth1"'

Now my brain is starting to wonder about the pros and cons of:

 - Policy Based Routing (PBR) (what you're doing)
 - Network Namespaces
 - Virtual Routing and Forwarding (a.k.a. L3MDEV)

Though, based on Anton's comment, I don't know that "ping -I" would have 
worked as desired.

That being said, it would be possible to have the NNS based gateways 
with proxy-arp enabled.  Thus you could probably do something like this:

ping -I dsl google.com
ping -I fbr google.com

Where dsl and fbr are vEth links into the respective NNSs w/ proxy-arp 
enabled.

I don't have enough experience with VRF (L3MDEV) to know how it would 
play different.  But I do think that VRF avoids some of the need for ip 
rules (PBR) to specify source IP or interface as it handles (some of?) 
that for you.



--
Grant. . . .
unix || die

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