Re: AW: AW: AW: bandwidth problems [Linux 2.4.20] [iptables 1.2.7a]

["John A. Sullivan III" <john.sullivan@nexusmgmt.com>]

On Thu, 2004-02-12 at 02:16, root@scheuchenstuel.com wrote:
> > > > > > > Hi!
> > > > > > >  
> > > > > > > My configuration:
> > > > > > > =================
> > > > > > > 
> > > > > > > O-------------o    O-----------------------o
> > > > > > > |    WinXP    |    |    eth0     |   eth1  |
> > > > > > > | 10.10.1.100 |----| 10.10.1.254 | D H C P |----INTERNET
> > > > > > > |             |    |             |         |
> > > > > > > O-------------o    O-----------------------o
> > > > > > >   My Computer           My NAT-Computer
> > > > > > > 
> > > > > > > NAT-Computer:
> > > > > > >   Linux 2.4.20-4GB
> > > > > > >   load average: 0.08, 0.05, 0.06
> > > > > > >   iptables v1.2.7a
> > > > > > > All the NICs I use are 3com 3C905-TX
> > > > > > > 
> > > > > > > When I do some bandwidth tests on the NAT-Computer
> > > > > > (provider's service
> > > > > > > page) my bandwidth is about 1MBit/second When I do the
> > > > same on my
> > > > > > > computer I only get about 100kbit/second
> > > > > > > 
> > > > > > > Now I wonder if there are any problems with my 
> > configuration...?
> > > > > > > Would be nice if you could help me...
> > > > > > > 
> > > > > > > Thanks in advance
> > > > > > > Florian St.
> > > > > > > 
> > > > > > > Root(AT)scheuchenstuel(DOT)com
> > > > > > > 
> > > > > > > 
> > > > > > > My iptables-configuration:
> > > > > > > ==========================
> > > > > > > 
> > > > > > > 
> > > > > > 
> > > > 
> > ####################################################################
> > > > > > ##
> > > > > > > ######
> > > > > > > ######
> > > > > > > 
> > > > > > > #!/bin/bash
> > > > > > > #
> > > > > > > 
> > > > > > > modprobe iptable_nat
> > > > > > > echo 1 > /proc/sys/net/ipv4/ip_forward
> > > > > > > 
> > > > > > > ########## CLEARING TABLES
> > > > > > > iptables -F
> > > > > > > iptables -t nat -F
> > > > > > > iptables -t mangle -F
> > > > > > > iptables -X
> > > > > > > 
> > > > > > > ########## SETTING POLICIES
> > > > > > > iptables -P INPUT DROP
> > > > > > > iptables -P OUTPUT ACCEPT
> > > > > > > iptables -P FORWARD DROP
> > > > > > > 
> > > > > > > ########## NAT
> > > > > > > iptables -A INPUT -i eth1 -m state --state
> > > > ESTABLISHED,RELATED -j
> > > > > > > ACCEPT iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE
> > > > > > > 
> > > > > > > ########## LOOPBACK SETTINGS
> > > > > > > iptables -A INPUT -i lo -j ACCEPT iptables -A INPUT -s 
> > > > > > > 127.0.0.1/32 -j ACCEPT
> > > > > > > 
> > > > > > > ########## EXTERNAL OPEN PORTS iptables -A INPUT -i eth1 -p 
> > > > > > > tcp --dport 80 -j ACCEPT
> > > > > > > 
> > > > > > > ########## INTERNAL OPEN PORTS iptables -A INPUT -s 
> > > > > > > 10.10.1.100/32 -j ACCEPT
> > > > > > > 
> > > > > > > ######### NAT FORWARDING
> > > > > > > iptables -A FORWARD -s 10.10.1.100/32 -j ACCEPT iptables -A
> > > > > > FORWARD -d
> > > > > > > 10.10.1.100/32 -j ACCEPT
> > > > > > > 
> > > > > > > 
> > > > > > 
> > > > 
> > ####################################################################
> > > > > > ##
> > > > > > > ######
> > > > > > > ######
> > > > > > 
> > > > > > The rules look a little unusual; in fact, they look downright 
> > > > > > dangerous.  You may want to read a good iptables 
> > tutorial such 
> > > > > > as the one by Oskar Andreasson.  You can find a link to it on 
> > > > > > the netfilter.org web site.  You can also find some slide
> > > > shows in the
> > > > > > training section at http://iscs.sourceforge.net
> > > > > > 
> > > > > > However, I do not think your rules would create a
> > > > throughput problem. 
> > > > > > How are you measuring your throughput?
> > > > > > --
> > > > > > John A. Sullivan III
> > > > > > Chief Technology Officer
> > > > > > Nexus Management
> > > > > > +1 207-985-7880
> > > > > > john.sullivan@nexusmgmt.com
> > > > > > ---
> > > > > 
> > > > > Now i tried to use a script suggested by Oskar Andreasson
> > > > > 
> > > > 
> > http://iptables-tutorial.frozentux.net/iptables-tutorial.html#RCFIRE
> > > > WA
> > > > > LLTXT
> > > > > 
> > > > > But the problem is still the same...
> > > > > I think there is another problem...
> > > > > 
> > > > > When i configure&start squid on the NAT-Computer i have
> > > > full bandwidth...
> > > > > 
> > > > > I don't know what to do anymore...
> > > > > 
> > > > > Thanks in advance
> > > > > Florian St.
> > > > How are you measuring your throughput? What happens if 
> > you don't use 
> > > > squid but allow direct (iptables protected) web access from the 
> > > > client?
> > > > --
> > > > John A. Sullivan III
> > > > Chief Technology Officer
> > > > Nexus Management
> > > > +1 207-985-7880
> > > > john.sullivan@nexusmgmt.com
> > > > ---
> > > 
> > > I use the bandwidth test-page of my provider...
> > > http://performance.chello.at:81
> > > 
> > > What do you mean with "direct" web access ?
> > > Web access via NAT ?
> > > I have entered the NAT-computer's IP as default gateway and the 
> > > provider's DNS-servers as DNS-servers on my PC.
> > > I think this is what you mean with direct access...
> > > 
> > > With this direct access i only get about 100kbit, when i 
> > use squid or 
> > > when i do the tests on the NAT-computer i have full 
> > Bandwidth (around 
> > > 1MBit/sec)
> > > 
> > > I think there is a general problem with my configuration, 
> > because the 
> > > bandwidth is no better with iptables-scripts which are 
> > known to work 
> > > fine...
> > > 
> > > I really don't know what to do anymore...
> > > 
> > > Thanks in advance
> > > Florian St.
> > 
> > As I look at it, unless you have significantly altered your 
> > scripts, you are probably not using Squid. I see no rule to 
> > redirect your web traffic to Squid.  What happens if you 
> > disable Squid?
> > 
> > --
> > John A. Sullivan III
> > Chief Technology Officer
> > Nexus Management
> > +1 207-985-7880
> > john.sullivan@nexusmgmt.com
> > 
> 
> Oh no - i never wanted a transparent proxy.
> I only activated squid to check is there is a general problem with the
> configuration of my NICs
> To test this I entered the NAT-Computer's IP-address as proxy-address in my
> browser
> 
> When I'm surfing with using the proxy - everything is fine - i have around
> 1MBit/sec
> When I access the internet directly (no proxy --> NAT) the speed is only
> about 100kBit/sec
> 
> Thanks in advance
> Florian St.

Ah, interesting.  What is the maximum bandwidth of your connection? I
know it's a silly question for a test site that I'd imagine is not using
cached data but could it be that the 1 Mbps results are somehow related
to the cache? What happens if you connect a station directly to the
Internet on your ISP's link? Do you see the same poor throughput? - John
-- 
John A. Sullivan III
Chief Technology Officer
Nexus Management
+1 207-985-7880
john.sullivan@nexusmgmt.com