[LARTC] DGD patch not detecting dead gateway

[Tom Lobato]

Manish Kathuria escreveu:
> On 2/8/07, Tom Lobato <tomlobato at gmail.com> wrote:
>
>>   Thank you for the script. I'm trying it.
>>
>>   Well, I made a simple modification and would like to hear opnions.
>>   Until now, I just added one more TESTIP, so I'm pinging one IP for 
>> each link.
>>   Also I'm using the IP instead name address, and used the DNS IP of 
>> each provider
>> for the ping. I made this because the ping to external sites (yahoo, 
>> google) is too slow
>> here, mainly when the link is under heavy load. So I'm afraid it can 
>> try ping
>> without success and "think" the link is down.
>
> I just used a popular external site because it may happen that
> connectivity from your location to the provider's DNS is there but the
> provider's link with the rest of the internet is down so even if you
> get a successful ping reply, the link isn't working in the real sense.

ok, I noted here my DNS server block pings (!) so I'm also using a site now.


> Also, I preferred using a name instead of IP address because there
> could be multiple IP addresses associated with the site name and they
> can change too. But I don't see anything wrong in your approach. What
> do you mean by slow ? I don't think ping reply time should be an
> issue. We are more concerned with the success. Obviously, it should
> not time out.

I agree, but here "slow == timeout" =) I'm suspecting the adsl modem is the
problem. I have two dynamic IP links, adsl/pppoe 400kbps and
cable-modem/dhcp 4Mbps.

Anyway, I changed my mind and will connect links directly to linux (no 
routers), with
the drawback of not have fixed IP/GW/MASK/NET's, but with advantages of 
need no routers,
need no port forwarding in routers, a more auto-sufficient solution.

So, I'm using your script as base (although I had made another, I liked 
yours), making scripts
for dhcp and pppoe create files with connection info, from where it 
reads data for set LB. If
someone more wants it, tell me and I send a mail.

I know I could apply the patchs and these scripts would too more simple, 
but the patch
does not detect fail if it is beyond the gateway.


>
> The ping reply times I get here for sites like www.yahoo.com and
> www.google.com are to the tune of 300 ms.

Here, without any internet use from localnet, i get ~150ms for both. So, 
really,
it appears I have another problem, not ping delay. Maybe too load on 
adsl link, although
I set weights 10 for cable link and 1 for adsl.





Tom Lobato