Difference between revisions of "Talk:Sysctl"

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(sysctl -p does not work)
('sysctl -p' does not work: re)
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== 'sysctl -p' does not work ==
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== 'sysctl -p' does not work ==  
 
The tip about reloading the configuration with 'sysctl -p' does not work. Complains about missing file "/etc/sysctl.conf". Probably does not work after systemd not reading from /etc/sysctl.conf... [[User:Olivervbk|olivervbk]] 23:12, 17 September 2013 (UTC-0300)
 
The tip about reloading the configuration with 'sysctl -p' does not work. Complains about missing file "/etc/sysctl.conf". Probably does not work after systemd not reading from /etc/sysctl.conf... [[User:Olivervbk|olivervbk]] 23:12, 17 September 2013 (UTC-0300)
 +
:Do you have the {{ic|/etc/sysctl.conf}}file replaced with a symlink to /etc/sysctl.d yet? I have not upgraded it yet. I was wondering about [https://wiki.archlinux.org/index.php?title=Sysctl&diff=275892&oldid=275542 this] edit as well. Was that proposed somewhere? I thought the systemd 207 brings the sysctl.d hierarchy to fix the settings. Usually its not a good idea to mod confs in /usr (as they will get lost not on reboots, but updates).  --[[User:Indigo|Indigo]] ([[User talk:Indigo|talk]]) 18:50, 18 September 2013 (UTC)

Revision as of 18:50, 18 September 2013

I can't imagine this being a very long article, but I do find it useful. I didn't have a clue what this command did until I came across it now. I recall it from my first time installing Arch, with regard to storing the volume levels in alsamixer. --Mustard 10:31, 22 October 2010 (EDT)

error: permission denied on key 'net.ipv4.conf.all.mc_forwarding'
error: permission denied on key 'net.ipv4.conf.default.mc_forwarding'

Are these not used any-more?

it's read only which might mean that it has to be changed while compiling the kernel, I'm not sure (it used to work), it is disabled by default anyway thestinger 16:39, 26 October 2010 (EDT)

net.ipv4.tcp_rfc1337

From kernel doc:

tcp_rfc1337 - BOOLEAN
	If set, the TCP stack behaves conforming to RFC1337. If unset,
	we are not conforming to RFC, but prevent TCP TIME_WAIT
	assassination.
	Default: 0

So, isn't 0 the safe value? Our wiki says otherwise. -- Lahwaacz (talk) 08:56, 17 September 2013 (UTC)

With setting 0 the system would 'assassinate' a socket in time_wait prematurely upon receiving a RST. While this might sound like a good idea (it frees up a socket quicker), it opens the door for tcp sequence problems/syn replay. Those problems were described in RFC1337 and enabling the setting 1 is one way to deal with them (letting TIME_WAIT packets idle out even if a reset is received, so that the sequence number cannot be reused meanwhile). The wiki is correct in my view. Kernel doc is wrong here - "prevent" should read "enable". --Indigo (talk) 21:12, 17 September 2013 (UTC)


'sysctl -p' does not work

The tip about reloading the configuration with 'sysctl -p' does not work. Complains about missing file "/etc/sysctl.conf". Probably does not work after systemd not reading from /etc/sysctl.conf... olivervbk 23:12, 17 September 2013 (UTC-0300)

Do you have the /etc/sysctl.conffile replaced with a symlink to /etc/sysctl.d yet? I have not upgraded it yet. I was wondering about this edit as well. Was that proposed somewhere? I thought the systemd 207 brings the sysctl.d hierarchy to fix the settings. Usually its not a good idea to mod confs in /usr (as they will get lost not on reboots, but updates). --Indigo (talk) 18:50, 18 September 2013 (UTC)