After layer 3 routing a large IPv6 assignment on an EX Juniper switch, the route forwarding table filled up and some entries corrupted or became otherwise invalid. We want to clear the whole table. How?

  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can post and accept your own answer. – Ron Maupin Dec 31 '20 at 21:26

It seems like it cleared up itself after deleting the prefixes from the configuration.

  • You should accept your answer so that the question doesn't keep popping up forever, looking for an answer. – Ron Maupin Jul 21 '17 at 7:35

Although your issue is cleared, here is your answer:

clear ethernet-switching table

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    This clear the MAC address table, not the forwarding (I.E. routing) table. – JFL Sep 19 '17 at 10:23
  • 1.If you read the link it says: "Clear learned entries, which are media access control (MAC) addresses, in the Ethernet switching table (also called the forwarding database table)" , so I'm not making this up. 2. Routing table is not the Forwarding table. 3. Share your references and expand on explanation, else you should delete your comment to not confuse people. – DRP Sep 20 '17 at 20:13
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    If you read the question it says "the route forwarding table" (and begin with " After layer 3 routing*". The question is obviously about the routing table and not about the MAC address table. My reference is the 802.1D document that define switch operation, in which the MAC address table is calle the filtering database. The fact that Juniper choose to call it a forwarding database is what cause confusion. In practice a fowarding database usually refer to the router FIB - Forwarding Information Database, built upon the various RIB - Routing Information Base. – JFL Sep 21 '17 at 6:45
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    Now I agree that the question is about a Juniper device and that in the linked document Juniper call the Mac Address Table the "forwarding database table", but since the question explicitly refers to the route forwarding table, it's not about this one. – JFL Sep 21 '17 at 6:46
  • @JFL In that case the title should be changed. I might have not come across yet, but so far Networking literature is often more consistent with either: routing table or forwarding table not route forwarding table, this is redundant and leads to misunderstanding. Even if you find commands that might tie that type of wording (i.e junipers: show route forwarding-table) the doc's will clearly state which table. – DRP Dec 20 '17 at 20:52

You can do this manually with this simple command:

clear route forwarding-table


As example(Juniper EX4200):

> clear route forwarding-table ?    

Possible completions: Destination prefix {master:0}

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