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Posted: Thu May 18, 2006 11:41 am
by integral

We are an ISP in hungary, in a small town. We use MT OS.
We are very contanted with this system, but we got a problem now:
We have 4 ADSL lines which we want to collapse with a MT.
The Load Balancing works very well. But one connection use more gateways that's why some connection oriented programs (for example FLASH-based, JAVA- chats, MSN, AOL IM, etc.) disconnects. Our question is: how can we fix this problem?
Does the MT OS support the: "PER DESTINATION LOAD BALANCING" technique? If yes, how?
We use Policy Routing now which statical assign one connenction to one gateway. But this couse sometimes traffic congestion on one gateway (1. ADSL line), pending the another one gateway (2. ADSL. line) has just a few traffic!
Is there any DYNAMIC connection redirection solution for fix this problem?

Thank You... Good work!

Posted: Thu May 18, 2006 2:28 pm
by janisk
you could try to route all that that way - that all msn alol im etc etc beeing routed through one ADSL line and all other traffic goes to 3 ADSL's with loadballancing

havent heard anything about "PER DESTINATION LOAD BALANCING"

maybe have to play with mangle and queues....

good luck searching


btw, there is no predictiona vailable for predicting how much bandwith will use connection, so there is onle one posibility - if you created connection through one GW than you have to keep that connection there

Posted: Thu May 18, 2006 3:47 pm
by nhalachev

havent heard anything about "PER DESTINATION LOAD BALANCING"
From Cisco Documentation:
"Per-destination load balancing means the router distributes the packets based on the destination address. Given two paths to the same network, all packets for destination1 on that network go over the first path, all packets for destination2 on that network go over the second path, and so on. This preserves packet order, with potential unequal usage of the links. If one host receives the majority of the traffic all packets use one link, which leaves bandwidth on other links unused. A larger number of destination addresses leads to more equally used links. To achieve more equally used links use IOS software to build a route-cache entry for every destination address, instead of every destination network, as is the case when only a single path exists. Therefore traffic for different hosts on the same destination network can use different paths. The downside of this approach is that for core backbone routers carrying traffic for thousands of destination hosts, memory and processing requirements for maintaining the cache become very demanding."

static solution :?

Posted: Thu May 18, 2006 4:33 pm
by integral
Thankx for the fast answers and ideas! :idea: BUT! the simple queues or queues tree and mangle are static solution :?

we need dynamic ones like cisco's CEF (cisco express forward) feature where the router dinamically create IP PAIRS (src-dest) and assign these ones to same gateway... another pairs will assigned to another one. :idea: so the connection oriented softwares will not disconnect anymore....

have MT such feature?

Posted: Thu May 18, 2006 5:32 pm
by macgaiver
I use routing-mark feature, devide all the traffic as I need, by mangling it in the prerouting chain, and thes send specific mark to specific gateway

Posted: Thu May 18, 2006 5:52 pm
by janisk
that was my idea to use conection mark and then add routing mark according to connection mark - this is easy :roll:

BUT there is one BUT.

If you create connection for large file transfer and create 2 of them and they both are connected through one connections - i think that your "o mighty CISCO" will not move other connection. THAT WAS WHAT I WAS SAYING.


due to lack of information for ANY connection information - it will be simple download of www page or some large file.

Posted: Fri May 19, 2006 8:53 am
by pekr
What about ECMP? According to docs, routerOS creates pairs of source-destingation adresses (not sure if ports included) and sends it thru particular gw. Not sure it is so with CISCO, but MT does it, so it could be sufficient, so no ICQ, FTP problems - IP pairs should be suitable for that (if different ports are not taken into account ....)