[BGPCEP-1014] as-path prepending with multiple instances of own AS number missing Created: 20/Aug/22 Updated: 24/Jan/24 |
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| Status: | Confirmed |
| Project: | bgpcep |
| Component/s: | BGP |
| Affects Version/s: | None |
| Fix Version/s: | 0.21.0, 0.19.9, 0.20.7 |
| Type: | Improvement | Priority: | High |
| Reporter: | Grzegorz Sulek | Assignee: | Unassigned |
| Resolution: | Unresolved | Votes: | 0 |
| Labels: | pick-next, pt | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Description |
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The as-path prepending functionality implemented in bgpcep is missing the feature to add more than one instance of own AS number defined in section section 5.1.2 of RFC4271: Whenever the modification of the AS_PATH attribute calls for including or prepending the AS number of the local system, the local system MAY include/prepend more than one instance of its own AS number in the AS_PATH attribute. This is controlled via local configuration. Currently it is possible to prepend only one instance of own AS to the path. |
| Comments |
| Comment by Robert Varga [ 20/Aug/22 ] |
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This has a tie-in with policies, as expressed in openconfig-rp-statement. That bit of code seems to do the right thing, assuming there are multiple actions are present. As a first step, I think we need some upfront design as to how this should work – either an explicit feature, or a policy thing. The other consequence of this is that path selection needs to treat the same ASN appearing consecutively in an AS_SEQUENCE is a single AS, not as an AS loop – otherwise we would end up disqualifying it rather than proceeding to check the AS distance. |