oxidecomputer / oxidecomputer/dendrite

Add tool to observe/calculate which ECMP path a packet will take

Open
#51 1 comment 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Rust
Stars
20
Forks
3
Avg merge
3d 11h
Merged PRs (30d)
4

Description

From @taspelund :

During a customer troubleshooting call today, a member of their networking team asked if we could tell them which link a flow would be leaving the sidecar from.

In this topology, each sidecar has 2 uplinks where we're learning a default route via BGP.

It would be really nice for troubleshooting and debugging to be able to calculate or observe which path a packet will take, without needing to do any kind of packet capture or ACL.

An example of this is the cl-ecmp-calc tool bundled with Cumulus Linux, which allows the user to supply hash function inputs (5 tuple, ingress interface, ToS value, IPv6 flow header, etc.) and have the relevant egress interface name returned to them.

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Use the two-uplink sidecar topology and BGP-learned default routes as the starting context. Review cl-ecmp-calc on Cumulus Linux for the proposed inputs, including the 5-tuple, ingress interface, ToS value, and IPv6 flow header; done means reporting the selected egress interface without packet capture or an ACL.

Written by the indexing model from the issue text.

Assessment

Tech stack
linux, rust
Domain
cli, networking
Issue type
Feature
Difficulty
5/5
Estimated time
Over a week
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.