Hi Friends,
I have a two customer. I sending full route tables. but my customer doesn’t want to full table because single . My ccr device changed default-originate = always but didn’t work. Do I need to make another settings extra? Cisco device commands is neighbor remote-as default-originate . How to sending defaul-route ?
Not sure if I’m getting your question properly.
If you don’t want to send full table to that customer, create an output filter tailored for him , then set it on its peer entry output filter.
Originating a default route prefix for a neighbor is a separate task from sending the contents of the BGP table.
Basically, if you have this option set to yes, then in addition to whatever prefixes are being sent to the neighbor, the router will originate a default route prefix with itself as the next hop, and toss that in the queue of things to send to the neighbor.
If the customer wants ONLY the default prefix, then two things need to happen on their session:
default GW information should be generated and included in their routes
all non-default-gw prefixes should be discarded by the out-filter for that customer.
In general, your customer-access routers with BGP should have a standard out-filter configured in them:
/routing filter
add action=accept chain=bgp-default-only prefix=0.0.0.0/0 prefix-length=0
add action=discard chain=bgp-default-only prefix=0.0.0.0/0 prefix-length=0-32
Setting the out-filter on the customer’s peer configuration to be this filter, plus enabling default-originate (if-installed is recommended) will give what you want.
Thank you ZeroByte. Can you give me bgp deploy advice on Mikrotik device ? my experience in Cisco product but cisco and mikrotik device implementation different.
In general, I’d say they’re not so different as far as the BGP theory itself goes. All of my BGP work with Mikrotik has been in labs, though, where all of my production BGP experience, like yours, is with Cisco.
The biggest difference I’ve seen (operationally) is that iBGP won’t forward a default-route prefix from eBGP into iBGP.
Mikrotik makes you originate a new default GW, but I don’t recommend doing this inside your iBGP because it can lead to routing loops. (I’ve created them in the lab myself) I think this is mostly intended to use with eBGP customer networks.
I think the biggest difference is that there isn’t a stand-alone BGP table in ROS like there is in Cisco, etc. BGP seems to work directly in the RIB table whereas Cisco only tries to push the winning routes from BGP into the RIB. ROS puts them all there, and marks the losers “inactive”
In general though, best practice seems to be best practice, regardless of platform.
Thanks for sharing your knowledge! Thanks for your advice. I do not know what you think but in such private matters ( bgp , mpls ) mikrotik wiki is not enough. Honestly , i do not want to be like Don Quijote .
You might want to download the CHR image for Virtualbox and set it up in GNS3 and do some messin’ around there.
I’ve had the most luck with the Virtualbox image (Qemu just acted strange - IPv6 package crashes, for instance) and it lets you dynamically connect/disconnect ethernet interfaces while the sim is running. (you can’t run headless mode though, or at least I had issues with network connectivity if I told GNS3 to hide the GUI)