SAP Traffic Conditional flow - URGENT Help

[nasr.khan]

Hi, I have got a scenario with tight goals.

DC----------Link 1-------------WH

DC----------Link 2-------------WH

Two point to point links between DataCenter and Warehouse. Link-1 I want to send all SAP Application traffic from DC to WH and its return traffic. All Other Traffic goes via Link-2.

Incase if Link-1 goes down then all traffic including SAP Application traffic should pass on Link-2.

Link-1 comes up then all SAP application traffic passes through it.

Is this doable without any manual process

[nasr.khan]

Hi Mr. Giuseppe

Correct me if this holds true, initial discussion was PBR solution and you adviced QOS solution and provided config help.

Due to packet loss issue, QOS doesnt look a solution for now. So was looking for PBR config help.

I am very thankful to your reply and you deserve 5+ on all reply.

Link you send me is more related to tracking of Links, but I am not clear how to send SAP traffic with link2 only and other traffic on Link1

Do advice.

[Giuseppe Larosa · Accepted solution]

Hello Nasr,

sorry for the disappointing tone I understand that you would like to verify what is suggested here.

yes, the thread has seen several developments and be aware that deploying QoS is still possible and recommended also with PBR as noted by Joseph in one of his last posts.

PBR as described in my post at time 10:17 is used to divert selected traffic flows over link2.

to be sure that all other traffic flows go on link1 is enough to make link1 more attractive for EIGRP routing protocol you use.

for this reason that final note saying that you still need to deploy EIGRP routing.

To do this you can use the bandwidth or delay commands in interface config mode only if link1 is not already preferred by EIGRP.

you can check this with

sh ip route for IP subnet in other side:

if you see a single IP route via link1 you are fine.

if you see two paths one via link1 and one via link2 of equal cost you need to manipulate BW or delay.

reduced BW or increased delay on link2 makes link1 preferred.

for PBR see

http://www.cisco.com/en/US/docs/ios/iproute/configuration/guide/irp_ip_prot_indep_ps6350_TSD_Products_Configuration_Guide_Chapter.html#wp1056703

also search netpro for other configurations of PBR on the archives

Hope to help

Giuseppe

[Joseph W. Doherty · Accepted solution]

BTW, if you're only using 12 to 35 K on a 5 Mbps link, and you're seeing drops, one might argue you should send all your traffic to the other link and stop paying for that "bad" link.

Also BTW, you might only be “using” 12 to 35 K because of a very poor quality link. Enough drops will tend to cause TCP flows to craw although perhaps without "breaking" the application.

Of course, many other things could be an issue too (or the root problem). You might want to reconsider Paolo's original suggestion and obtain some on-site consultation to review your situation.

[nasr.khan]

Thanks Both.

Great Help

I will do test and update on other post