imsnif/bandwhich

Retry DNS only after timeout

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#127 opened on Jan 16, 2020

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 (5 comments) (0 reactions) (0 assignees)Rust (7,686 stars) (237 forks)batch import
good first issuehelp wanted

Description

Right now, when we do our reverse-dns queries (getting the hostname of an ip address), if the request failed, we retry immediately. This can cause a lot of connections (also visible in the app!) to be opened if a request repeatedly fails.

It would be nice if we have some sort of progressive backoff mechanism for this... something like: wait for 1 second before retrying, then wait for 2, 4, etc.

Contributor guide

Tech stack
rust
Domain
backendperformance
Issue type
feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
basic Rust knowledgeunderstanding of DNS resolutionfamiliarity with retry/backoff concepts
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
50
Research direction
Examine the current DNS reverse lookup logic in bandwhich (likely in the dns module). Implement an exponential backoff strategy for retries: start at 1 second, then double after each failure. Ensure the backoff resets on success. Add configurable max delay and optional jitter. Test with simulated failures.