Difference between revisions of "Talk:Dnsmasq"

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(→‎Easier way to work with NetworkManager: Close finished.)
m (→‎Replace bind-interface w/ bind-dynamic in dnsmasq.conf: unsigned)
 
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== need information for fixed IPs ==
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== Force DNS cache persistence? ==
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when this is set in rc.conf I think that require :
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I've noticed that the DNS cache expires very quickly (less than 60 seconds) for many domains thereby defeating the purpose of caching it in the first place. Is there a way to force entries to last longer? [[User:Neounk|Neounk]] ([[User talk:Neounk|talk]]) 01:30, 31 March 2013 (UTC)
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{ echo "nameserver 127.0.0.1"; grep -v "^#" /etc/resolv.conf | head -2; } > /tmp/resolv.conf
 
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then backup /etc/resolv.conf and last :
 
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mv /tmp/resolv.conf /etc/resolv.conf
 
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--[[User:Sputnick|Sputnick]] 17:59, 1 August 2011 (EDT)
 
  
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== <s> Easier way to work with NetworkManager </s> ==
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== Dnsmasq and Pidgin/Gtalk ==
  
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If you add a line like
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Using dnsmasq for dns caching seems to break gtalk on pidgin. Editing /etc/dhcpcd.conf and adding
 +
option 'domainneed' '1' solves the issue on my machine.
  
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      dns=dnsmasq
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if others verify the issue and fix, maybe consider for addition to the wiki?
  
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to /etc/NetworkManager/NetworkManager.conf then not only will NetworkManager do the right thing about resolv.conf, it will also start up dnsmasq for us, which seems way easier. I just did it in my machine and it works OK. It uses a temp conf file for dnsmasq at /var/run/nm-dns-dnsmasq.conf, and resolv.conf has only 127.0.0.1. This is not OK if dnsmasq is used for DHCP server, but is very good for caching. As it seems to me this will be the most common pattern for people using NetworkManager, i added this at the start of the NetworkManager section, instead of at the end.
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[[User:LiamMcCalloway|LiamMcCalloway]] ([[User talk:LiamMcCalloway|talk]]) 01:10, 11 June 2013 (UTC) Liam
  
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Also, i feel that calling "DHCP config" the section about adding 127.0.0.1 to resolv.conf is very easy to confuse with configuring the DHCP functionality of dnsmasq itself. So i just changed the name to "resolv.conf".
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== Usage with libvirt ==
  
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[[User:Mrpsbrk|Mrpsbrk]] ([[User talk:Mrpsbrk|talk]]) 03:35, 30 August 2012 (UTC)
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Network-manager think if there is one running libvirt that he run this before. To fix conflicts between other dnsmasq, eg: used in [[libvirt]], you must run it externally.
  
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: Nice edits, Mrpsbrk. I hadn't known about this so this is *nice*. Cleanedup the page a bit so all is OK. Danke --[[User:Gen2ly|Gen2ly]] ([[User talk:Gen2ly|talk]]) 23:17, 30 August 2012 (UTC)
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We do '''not''' want change our resolv.conf automaticly.
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 +
{{hc|/etc/NetworkManager/NetworkManager.conf|<nowiki>
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[main]
 +
...
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dns=none
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</nowiki>}}
 +
 
 +
We put it manually here.
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{{hc|/etc/resolv.conf.head|2=
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nameserver 127.0.0.1
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}}
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The interface to bind and bind it even if there is second dnsmasq runned on computer.
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{{hc|/etc/NetworkManager/dnsmasq.d/bind-interface.conf|2=
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interface=lo
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bind-interface
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}}
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This start service if interface is up. This service can start only once before stop which will be initiate by systemd on restart/shutdown.
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 +
{{hc|/etc/NetworkManager/dispatcher.d/10_dnsmasq|2=
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#!/bin/sh
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if [ -n "$2" ] && [ "$2" = "up" ]; then # $INTERFACE is up
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systemctl start NetworkManager-dnsmasq.service
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fi
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}}
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Systemd service.
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{{hc|/etc/systemd/system/NetworkManager-dnsmasq.service|2=
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[Unit]
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Description=A lightweight DHCP and caching DNS server
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After=network.target
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Documentation=man:dnsmasq(8)
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[Service]
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Type=dbus
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BusName=uk.org.thekelleys.dnsmasq
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ExecStartPre=/usr/bin/dnsmasq --test
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ExecStart=/usr/bin/dnsmasq -k --enable-dbus --user=dnsmasq --pid-file --conf-dir=/etc/NetworkManager/dnsmasq.d/
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ExecReload=/bin/kill -HUP $MAINPID
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}}
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00:03, 25 March 2016‎ 3ED
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== Replace bind-interface w/ bind-dynamic in dnsmasq.conf ==
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 +
I was running into an issue where dnsmasp would try to bind to my device before it was up, and the service would crash. After some research it seems that there is a "bind-dynamic" option that does not require the device to be up (and can simply bind the socket when it is actually connected)
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https://bugzilla.redhat.com/show_bug.cgi?id=1502081
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---
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''I think this issue is better solved by using bind-dynamic instead of bind-interfaces. network-online.target is not used intentionally. If system is configured to use dnsmasq as DNS resolver of the system, network-online.target may not be active until dnsmasq is ready. It must not wait for network-online.target by default.[bind-dynamic] allows start of dnsmasq even when eth0 is still down. As soon as it is up, it will bind the interface and listen on it. I think this is exactly what is required in this case.''
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Seems better suited for usage, no?
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{{unsigned|22:17, 16 May 2018‎|Kuzyn}}

Latest revision as of 06:22, 17 May 2018

Force DNS cache persistence?

I've noticed that the DNS cache expires very quickly (less than 60 seconds) for many domains thereby defeating the purpose of caching it in the first place. Is there a way to force entries to last longer? Neounk (talk) 01:30, 31 March 2013 (UTC)

Dnsmasq and Pidgin/Gtalk

Using dnsmasq for dns caching seems to break gtalk on pidgin. Editing /etc/dhcpcd.conf and adding option 'domainneed' '1' solves the issue on my machine.

if others verify the issue and fix, maybe consider for addition to the wiki?

LiamMcCalloway (talk) 01:10, 11 June 2013 (UTC) Liam

Usage with libvirt

Network-manager think if there is one running libvirt that he run this before. To fix conflicts between other dnsmasq, eg: used in libvirt, you must run it externally.

We do not want change our resolv.conf automaticly. 

/etc/NetworkManager/NetworkManager.conf
[main]
...
dns=none

We put it manually here. 

/etc/resolv.conf.head
nameserver 127.0.0.1

The interface to bind and bind it even if there is second dnsmasq runned on computer. 

/etc/NetworkManager/dnsmasq.d/bind-interface.conf
interface=lo
bind-interface

This start service if interface is up. This service can start only once before stop which will be initiate by systemd on restart/shutdown. 

/etc/NetworkManager/dispatcher.d/10_dnsmasq
#!/bin/sh
if [ -n "$2" ] && [ "$2" = "up" ]; then # $INTERFACE is up
	systemctl start NetworkManager-dnsmasq.service
fi

Systemd service. 

/etc/systemd/system/NetworkManager-dnsmasq.service
[Unit]
Description=A lightweight DHCP and caching DNS server
After=network.target
Documentation=man:dnsmasq(8)

[Service]
Type=dbus
BusName=uk.org.thekelleys.dnsmasq
ExecStartPre=/usr/bin/dnsmasq --test
ExecStart=/usr/bin/dnsmasq -k --enable-dbus --user=dnsmasq --pid-file --conf-dir=/etc/NetworkManager/dnsmasq.d/
ExecReload=/bin/kill -HUP $MAINPID

00:03, 25 March 2016‎ 3ED

Replace bind-interface w/ bind-dynamic in dnsmasq.conf

I was running into an issue where dnsmasp would try to bind to my device before it was up, and the service would crash. After some research it seems that there is a "bind-dynamic" option that does not require the device to be up (and can simply bind the socket when it is actually connected)

https://bugzilla.redhat.com/show_bug.cgi?id=1502081

---

I think this issue is better solved by using bind-dynamic instead of bind-interfaces. network-online.target is not used intentionally. If system is configured to use dnsmasq as DNS resolver of the system, network-online.target may not be active until dnsmasq is ready. It must not wait for network-online.target by default.[bind-dynamic] allows start of dnsmasq even when eth0 is still down. As soon as it is up, it will bind the interface and listen on it. I think this is exactly what is required in this case.

Seems better suited for usage, no?

—This unsigned comment is by Kuzyn (talk) 22:17, 16 May 2018‎. Please sign your posts with ~~~~!

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