---
name: "dnsreplay"
section: "8"
platform: "linux"
package: "pdns-server"
version: "3.4.1-4+deb8u8"
release: "Debian 8 (Jessie)"
platforms: ["linux"]
url: "https://new.carta.tech/dnsreplay/8"
---

# dnsreplay(8)

A PowerDNS nameserver debugging tool

## NAME

dnsreplay - A PowerDNS nameserver debugging tool

## SYNOPSIS

**dnsreplay *\[options\]* *filename* *ip-address* *\[port\]***

## DESCRIPTION

This program takes recorded questions and answers and replays them to a specified  nameserver and reporting afterwards which percentage of answers matched, were worse or better.

*filename* is expected to be an PCAP file. The queries are send to the DNS server specified as  *ip-address* and *\[port\]*. *ip-address* is mandatory. If  *\[port\]* is omitted, 53 will be used. dnsreplay compares the answers and some other metrics with the actual ones with those found in the dumpfile.

By default it only replay queries with recursion-desired flag set.

## OPTIONS

- **--help \| -h**

  Show summary of options.

- **--packet-limit *num***

  Stop after replaying *num* packets. Default for *num* is 0, which means no limit.

- **--quiet *flag***

  If *flag* is set to 1. dnsreplay will not be very noisy with its output. This is the default.

- **--recursive *flag***

  If *flag* is set to 1. dnsreplay will only replay queries with recursion desired flag set. This is the default.

- **--speedup *factor***

  Replay queries with this speedup factor. Default is 1.

- **--timeout-msec *time***

  Wait at least this many milliseconds for a reply. Default is 500.

## BUGS

dnsreplay has no certain handling for timeouts. It handles around at most 65536 outstanding answers.

## SEE ALSO

pcap(3PCAP), [tcpdump(8)](/tcpdump/8.md), dnswascher(8)

## AUTHORS

This manpage was written by Joerg Jungermann (jj+debian At borkum.net) for the  Debian Project and the PowerDNS versatile DNS server.