Disable reverse lookup in rsync daemon

Question

I'm having an issue with some rsync modules being served through rsync --daemon

This lines are from my /var/log/rsyncd.log file :

2013/02/08 12:15:28 [13174] name lookup failed for XXX.XXX.XXX.XXX: Name or service not known
2013/02/08 12:15:28 [13174] connect from UNKNOWN (XXX.XXX.XXX.XXX)

From rsyncd.conf man page:

reverse lookup

Controls whether the daemon performs a reverse lookup on the client's IP address to determine its hostname, which is used for "hosts allow"/"hosts deny" checks and the "%h" log escape. This is enabled by default, but you may wish to disable it to save time if you know the lookup will not return a useful result, in which case the daemon will use the name "UNDETERMINED" instead.

If this parameter is enabled globally (even by default), rsync performs the lookup as soon as a client connects, so disabling it for a module will not avoid the lookup. Thus, you probably want to disable it globally and then enable it for modules that need the information.

So I added the following line to the global conf in /etc/rsyncd.conf

reverse lookup = no

But, when I stopped and started the daemon this lines where added to the log file:

2013/02/08 12:47:17 [13675] Unknown Parameter encountered: "reverse lookup" 
2013/02/08 12:47:17 [13675] IGNORING unknown parameter "reverse lookup" 
2013/02/08 12:47:17 [13676] rsyncd version 3.0.7 starting, listening on port 873

This is the version installed on my server:

rsync version 3.0.7 protocol version 30

The [Ubuntu manpage for 3.0.7](http://manpages.ubuntu.com/manpages/lucid/en/man5/rsyncd.conf.5.html) doesn't list this option. Are you referring to the manpage from the same package as the version you're using? — mgorven, Feb 08 '13 at 19:25
No, I was referring to an online man page since I did't install `man`. My bad — Jorge V., Feb 08 '13 at 20:22

score 7 · Accepted Answer · edited Jun 11 '20 at 10:02

7

The reverse lookup option is only present in the upcoming 3.1.0 release:

NEWS for rsync 3.1.0 (UNRELEASED)

Added the "reverse lookup" parameter to the rsync daemon config file to allow reverse-DNS lookups to be disabled.

edited Jun 11 '20 at 10:02

Community

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answered Feb 08 '13 at 19:30

mgorven

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Now it makes sense – Jorge V. Feb 08 '13 at 20:17

score 5 · Answer 2 · answered Feb 08 '13 at 19:26

5

I don't think the option for turning off reverse dns lookup exists in rsync daemon. What you can do instead is put the client hosts and IP addresses in /etc/hosts , of course assuming that your clients have static IP and are a few hosts.

answered Feb 08 '13 at 19:26

Daniel t.

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score -3 · Answer 3 · answered Jul 24 '15 at 08:35

-3

Option "reverse lookup" only add on version from 3.1.0

answered Jul 24 '15 at 08:35

Người Hòai Cổ

1

This was answered already, two years ago. – Sven Jul 24 '15 at 09:02

Disable reverse lookup in rsync daemon

3 Answers3