[V18 SD WAN] Application routing does not work

Hi guillaume bottollier 

Please refer to the video - https://www.youtube.com/watch?v=TolZsFNbBuM&list=PL_b4O8ZwWOqu3eDmTuC22czPQuH9furOx&index=6

Please refer to the articles

https://community.sophos.com/products/xg-firewall/f/network-and-routing/118714/sd-wan-policies-my-experience-so-far

https://community.sophos.com/products/xg-firewall/sfos-eap/sfos-v18-early-access-program/f/feedback-and-issues/116166/some-confusion-about-the-new-sdwan-routing-feature

hello Keyur 

Thanks for the links, but this does not help me to solve this issue, i followed the video to build my sd route policy, which is the exact thing i want to do !

but this does not work, streaming is routed regarless of the policy through the backup link.

Hi,

with that rule order nothing will get to the second rule, so as it is the  https and http will go out the any rule.

Ian

Some more information.

I have created a rule for ICMP to it's easier to test. A tracert to google.com responds exactly the way I would expect the rule to work; when I set the gateway to DSL (Verizon) it follows that route and when I set it to LTE it uses Sprint. The results are very consistent:

6 64 ms 50 ms 50 ms sl-crs1-dc-.sprintlink.net 
7 76 ms 41 ms 38 ms sl-mst30-ash-be14.sprintlink.net

4 40 ms 35 ms 38 ms g101-0-0-2.rcmdva-lcr-22.verizon-gni.net

In other words, the routing engine functions properly. However, targeting applications fails.

I have not yet tried separating other types of traffic.

with that rule order nothing will get to the second rule, so as it is the  https and http will go out the any rule.

What I have now is:

1. Rule 1 - criterion is Application (Streaming). WAN interface: DSL
2. Rule 2 - HTTP and HTTPS. WAN interface: LTE

I assumed that the application/streaming rule would take precedence since it's the first rule.

Are you saying that rule 2 (HTTP/HTTPS) takes precedence even though the first rule specifies the application?

If this is the case, how would I configure the rules so Streaming is routed to a specific interface?

Hi,

what I am saying is the rule order takes precedence, not the rule number. You had "any" service in the higher placed rule which would allow http/s out.

Also I assume you have a linked NAT rule for each firewall rule?

Ian

what I am saying is the rule order takes precedence, not the rule number. You had "any" service in the higher placed rule which would allow http/s out.

Also I assume you have a linked NAT rule for each firewall rule?

OK - I understand where you're coming from now. However, the first rule "Force streaming to DSL", while having the criterion "any service", does have the Application Object set to "Streaming Media".

That's why I figured this rule would fire on streaming media.

As far a the NAT-config, I'd have to take a look. I haven't looked at it since I upgraded from v17.

Hi Arie,

this is a comment and I cannot remember where I got it from. "The application function in  a firewall rule is primarily designed as DENY and is not very good at ALLOW."

I would suggest you change your destination to some streaming sites and add the ports they use to improve your testing.

Ian

this is a comment and I cannot remember where I got it from. "The application function in  a firewall rule is primarily designed as DENY and is not very good at ALLOW."

I would suggest you change your destination to some streaming sites and add the ports they use to improve your testing.

Hi Ian,

Okay - I remember reading something like that also, but since Sophos has instructions specifically for the scenario in question (routing streaming media) I figured this would be fully supported. Judging by the questions people are posting about it I wonder if it is all working as intended, though.

By the way, here's the official Sophos video I am referring to: https://vimeo.com/390800287.

As far as adding the ports for streaming, I doubt that would work since the initial client request for the video would be over 443.

I have, however, added a category "Search Engines" in the application section. No luck so far, though. It's possible that I need to wait for the TTL to expire (3600 seconds). Aside from rebooting the XG I don't know of a way to clear the tables. Anything in the CLI?

Hi Aria,

I had some issues with that video, it does not really apply to the v18 GA SR2 eg there is no troubleshooting tab.

I would suggest you try changing your destination to a specific site.

I have one of my streaming radio station applications point at the station server, it also uses a specific port.

If you have a rule allowing https (443) to allow initial connection/setup and then a rule with the actual application streaming port and redirect that using SD-WAN.

Ian

Late breaking thought - something you said in an earlier post about migration, have you deleted all of your SD-WAN migration policies?

hi rfcat_vk hi Arie 

After doing some debug with sophos support, it's clear that this SDWAN routing by application feature is a crap... by design.

When you are going on youtube website, XG will consider trafic is port 443 for sdwan routing policy, and not youtube video application.

this feature is useless, unless a real improvement on the way it has been implemented.

Hi Ian,

I had some issues with that video, it does not really apply to the v18 GA SR2 eg there is no troubleshooting tab.

I had noticed the discrepancy also, but given that Sophos went through the trouble of specifically linking this video from the admin interface you'd think the information would be reliable.

I would suggest you try changing your destination to a specific site.

That may be the only way to get this to work.

I have one of my streaming radio station applications point at the station server, it also uses a specific port.

Does it use a specific port even for the client request? I.e. not 80/443?

If you have a rule allowing https (443) to allow initial connection/setup and then a rule with the actual application streaming port and redirect that using SD-WAN.

Would that work? I'd imagine that the behavior would be unpredictable at best if 'regular' (443/80) traffic goes out on a different egress IP-address than you want the response (i.e. streaming) to come in on. The server is going to send the response to whichever public address made the request. 

Late breaking thought - something you said in an earlier post about migration, have you deleted all of your SD-WAN migration policies?

I've started looking at that a bit more. After migration I cleaned up a bunch of stuff, but it looks like I never got around to cleaning up NAT. There might be more migration-stuff lurking in other places.

I did, however, clone my FW-rule and create a new NAT (MASQ) policy for it to replace the migrated policy. Unfortunately, no luck so far.

Troubleshooting is cumbersome, though, since there doesn't seem to be a way to clear the persistence other than rebooting the XG.

Hi Ian,

I had some issues with that video, it does not really apply to the v18 GA SR2 eg there is no troubleshooting tab.

I had noticed the discrepancy also, but given that Sophos went through the trouble of specifically linking this video from the admin interface you'd think the information would be reliable.

I would suggest you try changing your destination to a specific site.

That may be the only way to get this to work.

I have one of my streaming radio station applications point at the station server, it also uses a specific port.

Does it use a specific port even for the client request? I.e. not 80/443?

If you have a rule allowing https (443) to allow initial connection/setup and then a rule with the actual application streaming port and redirect that using SD-WAN.

Would that work? I'd imagine that the behavior would be unpredictable at best if 'regular' (443/80) traffic goes out on a different egress IP-address than you want the response (i.e. streaming) to come in on. The server is going to send the response to whichever public address made the request. 

Late breaking thought - something you said in an earlier post about migration, have you deleted all of your SD-WAN migration policies?

I've started looking at that a bit more. After migration I cleaned up a bunch of stuff, but it looks like I never got around to cleaning up NAT. There might be more migration-stuff lurking in other places.

I did, however, clone my FW-rule and create a new NAT (MASQ) policy for it to replace the migrated policy. Unfortunately, no luck so far.

Troubleshooting is cumbersome, though, since there doesn't seem to be a way to clear the persistence other than rebooting the XG.