How to change MAX number of network connections

I have an update process that uses up all my connections. It then has to
sit and wait for one of them to timeout before it can go on.

Is this a kernel setting?

whoha <(E-Mail Removed)> said:
>I have an update process that uses up all my connections. It then has to
>sit and wait for one of them to timeout before it can go on.
>
> Is this a kernel setting?

You can view and set this via the (virtual) file
/proc/sys/net/ipv4/ip_local_port_range .

At least some systems also have the sysctl command for making changes
to things within /proc/sys . To view current settings, either just
'cat' the file, or do:
sysctl net.ipv4.ip_local_port_range

That'll show which ports are available for connections to remote machines.
Change can be done with sysctl or by echoing desired numbers into the file.
Any change in /proc/sys is permanent until next reboot; see the manuals
for your distribution on how to automate /proc/sys settings during bootup.
--
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Juha Laiho wrote:
> whoha <(E-Mail Removed)> said:
>
>>I have an update process that uses up all my connections. It then has to
>>sit and wait for one of them to timeout before it can go on.
>>
>> Is this a kernel setting?
>
>
> You can view and set this via the (virtual) file
> /proc/sys/net/ipv4/ip_local_port_range .
>
> At least some systems also have the sysctl command for making changes
> to things within /proc/sys . To view current settings, either just
> 'cat' the file, or do:
> sysctl net.ipv4.ip_local_port_range
>
> That'll show which ports are available for connections to remote machines.
> Change can be done with sysctl or by echoing desired numbers into the file.
> Any change in /proc/sys is permanent until next reboot; see the manuals
> for your distribution on how to automate /proc/sys settings during bootup.

Hi When I do that, I get: 1024 4999

What's the logic behind increasing it? if i add like 3 0's to the end
of each number would that increase network proformence but hurt other
things(i.e. increase memory usage,etc..)?

I just wanted to ask before I changed anything.

Thanks!

On Tue, 08 Feb 2005 08:28:34 -0500, whoha <(E-Mail Removed)> wrote:
| I have an update process that uses up all my connections. It then has to
| sit and wait for one of them to timeout before it can go on.
|
| Is this a kernel setting?


How do you know that "using up all your network connections" is the real problem?

What is the error message you receive?


--
Reverend Paul Colquhoun, ULC. http://andor.dropbear.id.au/~paulcol
Asking for technical help in newsgroups? Read this first:
http://catb.org/~esr/faqs/smart-questions.html#intro

On Tue, 08 Feb 2005 23:06:55 -0500, Gautam Bakshi <(E-Mail Removed)> wrote:
| Juha Laiho wrote:
|> whoha <(E-Mail Removed)> said:
|>
|>>I have an update process that uses up all my connections. It then has to
|>>sit and wait for one of them to timeout before it can go on.
|>>
|>> Is this a kernel setting?
|>
|>
|> You can view and set this via the (virtual) file
|> /proc/sys/net/ipv4/ip_local_port_range .
|>
|> At least some systems also have the sysctl command for making changes
|> to things within /proc/sys . To view current settings, either just
|> 'cat' the file, or do:
|> sysctl net.ipv4.ip_local_port_range
|>
|> That'll show which ports are available for connections to remote machines.
|> Change can be done with sysctl or by echoing desired numbers into the file.
|> Any change in /proc/sys is permanent until next reboot; see the manuals
|> for your distribution on how to automate /proc/sys settings during bootup.
|
| Hi When I do that, I get: 1024 4999
|
| What's the logic behind increasing it? if i add like 3 0's to the end
| of each number would that increase network proformence but hurt other
| things(i.e. increase memory usage,etc..)?
|
| I just wanted to ask before I changed anything.


These are lowest & highest available port numbers. Increasing the lower
number is pointless. The maximum possible value is 2^16 - 1 (65535).


--
Reverend Paul Colquhoun, ULC. http://andor.dropbear.id.au/~paulcol
Asking for technical help in newsgroups? Read this first:
http://catb.org/~esr/faqs/smart-questions.html#intro

Paul Colquhoun wrote:
> On Tue, 08 Feb 2005 08:28:34 -0500, whoha <(E-Mail Removed)> wrote:
> | I have an update process that uses up all my connections. It then has to
> | sit and wait for one of them to timeout before it can go on.
> |
> | Is this a kernel setting?
>
>
> How do you know that "using up all your network connections" is the real problem?
>
> What is the error message you receive?
>
>
I'm fishing I have tried lots of things like DNS, updates, reverting to
an older kernel, etc. . Here's the info I have

I have a server that worked great for about 2 years then
started to show the following problems.
+ Starting windows from desktop [like a terminal window
or mozilla or text editor] takes about 2 min's to open.

+ typing in passwords or url's you are typing in a black hole
takes 30 sec's for text to appear on screen. This is not the
case in a terminal window but rather in mozilla or X.

+ while running an update script that makes many connections to a umich
server it will sit at the 141.211.xxx.xxx:80 lines for 2-3 min's
then connect and
fly through the download and install only to wait at the next
connect line
again. Time to run this script has changed from 50-70 sec's to 350-450
sec's

info:
Linux zorkmonitor 2.4.20-37.9.legacysmp #1 SMP Mon Sep 27 19:29:13 EDT
2004 i686 i686 i386 GNU/Linux

XFree86 Version 4.3.0 (Red Hat Linux 9 release: 4.3.0-2.90.55)
Release Date: 15 August 2003
X Protocol Version 11, Revision 0, Release 6.6
Build Operating System: Linux 2.4.21-2.ELsmp i686 [ELF]
Build Date: 12 February 2004
Build Host: porky.devel.redhat.com

NOTE this top snip was taken while update process was running

89 processes: 88 sleeping, 1 running, 0 zombie, 0 stopped
CPU0 states: 4.2% user 1.1% system 0.0% nice 0.0% iowait
94.0% idle
CPU1 states: 2.1% user 1.1% system 0.0% nice 0.0% iowait
96.1% idle
Mem: 254684k av, 231628k used, 23056k free, 0k shrd,
37868k buff
144552k actv, 40360k in_d, 1928k in_c
Swap: 522104k av, 3724k used, 518380k free
111020k cached


PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME CPU COMMAND
1470 root 15 0 18800 14M 660 S 5.3 5.6 0:45 0 X
1573 root 15 0 6004 6004 3904 S 0.9 2.3 0:02 0 metacity
1595 root 15 0 8792 8788 5540 S 0.9 3.4 0:09 0
gnome-termina
1575 root 15 0 2852 2848 1824 S 0.5 1.1 0:06 1 magicdev
1577 root 15 0 10368 10M 5888 S 0.5 4.0 0:39 0
gnome-panel
1651 root 15 0 1088 1088 868 R 0.3 0.4 0:00 1 top
1581 root 15 0 3780 3780 2608 S 0.1 1.4 0:04 0 eggcups
1585 root 15 0 10972 10M 4784 S 0.1 4.3 0:09 0
rhn-applet-gu


sniff done during this time shows lots of nop's and not much else.