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Correct way & which parameter to disable tcp_timestamp in Solaris x86

sunhux
sunhux asked
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Last Modified: 2014-11-18
I'm on Solaris x86  10 & 11.

Q1:
What's the right way to disable tcp_timestamp?

http://www.cns.nyu.edu/~fan/sun-docs/sol10-01-13/html/E37386/chapter4-31.html
Above link does not have any parameters for tcp_timestamps (guess there is an 's' at
the back) & the closest is tcp_tstamp_always

Q2:
At some other URLs, it gave the same method as setting it in RHEL ie
   echo 0 > /proc/sys/net/ipv4/tcp_timestamps     &
add line below to etc/sysctl.conf (create the file if it does not already exist):
   net.ipv4.tcp_timestamps = 0

Q3:
if sysctl.conf does not exist, is that the only line to add in or we ought to
add a few other lines to make the parameters "balanced".  I recall I used
to tweak /etc/system & several parameters need to be inside this system file
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Commented:
I am not sure about Solaris, but in Linux you would edit the /etc/sysctl.conf file.  And edit or add the following line to make it look like this:

net.ipv4.tcp_timestamps = 0

Author

Commented:
Thanks;  but I'll need it specifically for Solaris x86  Ver 10 & 11
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Commented:
I'm confused as understand from Savone's link the parameter is tcp_timestamps but Gheist's link  indicates  tcp_tstamp_always

So if the file sysctl.conf is not there, I'll need to create one & enter all
those lines indicated by Savone & not just one line?

Author

Commented:
Instead of sysctl.conf, link below indicates /etc/system :
http://slaptijack.com/system-administration/solaris-tcp-performance-tuning/

I'm on Solaris x86  Ver 10 & 11  (running in VMs)

Author

Commented:
I'm confused, which of the 3 variations below to choose (note that
I don't have the luxury to test it out) :

echo 0 > /proc/sys/net/ipv4/tcp_tstamp_always
     OR
echo 0 > /proc/sys/net/ipv4/tcp_timestamps
     OR
sudo ndd -set /dev/tcp tcp_tstamp_if_wscale 0   ??

Author

Commented:
Does Solaris x86  V10/11 comes preinstalled with iptables ?
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Commented:
The link I gave you is from Oracle directly.

"Additionally, create an /etc/sysctl.conf file and append it with the following values"

You have to CREATE the file.

You ONLY have to add the lines that pertain to what you are trying to do, not ALL of them.

In your case this line:
net.ipv4.tcp_timestamps = 0

Good luck!

Author

Commented:
But the link Gheist gave is also from Oracle

If only I have the luxury of testing them out...
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Commented:
The slaptijack link is from me.

What Gheist gave & it indicates another parameter tcp_tstamp_always :
https://docs.oracle.com/cd/E19455-01/816-0607/6m735r5ga/index.html

Author

Commented:
Managed to get hold of a Solaris x86 to verify:

ndd -set /dev/tcp tcp_tstamp_if_wscale 1
& add the above line into /etc/system

(I wud rather add it as /etc/init.d/S99diststamp startup script

Author

Commented:
No iptables in our Solaris x86

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