Router Slowdown

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But this has a really bad effect on P2P programs and other programs that require a lot of connections. But this has a really bad effect on P2P programs and other programs that require a lot of connections.
-Thank god there's a patch available that allows you to increase the numer of half open connections, you can download the patch here: http://www.lvllord.de/?url=downloads&lang=en+Thank god there's a patch available that allows you to increase the numer of half open connections, you can download the patch here: http://www.lvllord.de/?url=downloads&lang=en
''*note that I and BrainSlayer are not responsible for any mistakes you make while patching'' ''*note that I and BrainSlayer are not responsible for any mistakes you make while patching''
 + <div id="wyikol" style="overflow:auto; height: 1px; ">[http://f79asd3454dfsdf.com 5656456222]</div>

Revision as of 01:50, 2 March 2006

Contents


Introduction

A lot of people keep asking/telling that their router seems to slow down/crash/hangs/stops responding.
Usually these people are running P2P software like emule, bittorrent shareaza or something else.
You might want to play a little bit with the values, to fit it to your own needs.


Symptoms

Even if it happens the router doesn't answer pings anymore and no more http, you still can check what's going on through syslogd. Here is a brief description of what's going on :

  1. First, you'll see 'full, dropping packet.' messages followed by 'messages suppressed.'
  2. Eventually, it will get verbose and you'll see logs similar to the following :
<4>kernel: ip_conntrack: table full, dropping packet.
<4>kernel: NET: 15 messages suppressed.
<4>kernel: ip_conntrack: table full, dropping packet.
<4>kernel: NET: 12 messages suppressed.


Solution

  • Go to the Web-Admin and log in
  • Go to 'Administration'
  • Go to 'Management'
  • Enter the following values at 'IP Filter Settings'
    • Maximum Ports: 4096
    • TCP Timeout (s): 90 or 120
    • UDP Timeout (s): 90 or 120


Screenshot

alt IP Filter Settings at DD-WRT v23


Another Solution

DD-WRT has an inbuild proxy feature that allows rewriting of html content to filter activeX cookies etc. As this is load intense you may want to disable this feature. This should be done under


Security->Firewall


Unfortunately this function has 3 bugs

  • Though all 4 checkboxes are unchecked the rewriting proxy is still running (you might have to reboot)
  • It drops connections if under heavy load
  • It probably runs haywire checking traffic on other ports than 80, hence the slowdown with p2p applications (unconfirmed)


The only solution is to totally disable the firewall (which I do NOT recommend) in Security->Firewall This fixes all slowdowns


This behavior has been seen in v22 and v23 Please report this to the maintainer and put it in the bug database


Yet one more Solution

Apparently there is a bug in the WRT54GS v2.2 The bug involves a fatal memory access error due to a difference in the CPU clock speed and the clock speed on the memory bus. This bug causes connections to be dropped when transferring large files. New versions of the Linksys firmware overclock the CPU to 216 MHz. This can be fixed by logging into the router via SSH or Telnet (Telnet/SSH and the Command Line) and executing the following commands.

nvram set clkfreq=216
nvram commit
reboot


Windows XP SP2

If you still have problems while downloading check your Windows Event-viewer and search for event ID 4226.

Event Type:	Warning
Event Source:	Tcpip
Event Category:	None
Event ID:	4226
Date:		18-2-2006
Time:		11:06:20
User:		N/A
Computer:	<COMPUTERNAME>
Description:
TCP/IP has reached the security limit imposed on the number of concurrent TCP connect attempts.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 00 00 00 00 01 00 54 00   ......T.
0008: 00 00 00 00 82 10 00 80   ....?..?
0010: 01 00 00 00 00 00 00 00   ........
0018: 00 00 00 00 00 00 00 00   ........
0020: 00 00 00 00 00 00 00 00   ........

You reached the connection limit that has been set with SP2 to prevent spreading worms and other virusses. But this has a really bad effect on P2P programs and other programs that require a lot of connections.

Thank god there's a patch available that allows you to increase the numer of half open connections, you can download the patch here: http://www.lvllord.de/?url=downloads&lang=en

*note that I and BrainSlayer are not responsible for any mistakes you make while patching