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Permanent mtu adjustment
Authored by: pb on Oct 19, '01 05:58:06PM
Here's how to make your new mtu setting persistent. Log in using your administrator account and open a Terminal window. Enter the following:

sudo pico /etc/ppp/ip-up

Type the following two lines into the new file you just created:
#!/bin/sh
/sbin/ifconfig ppp0 mtu 1492


Save the file using Ctrl-O (Write Out) then exit pico using Ctrl-X. Next you must make the file you just created executable. Enter this command:

sudo chmod 755 /etc/ppp/ip-up

That's it. What this does is create a shell script called ip-up that readjusts your mtu on your pppoe interface. The ppp daemon which controls your pppoe connection will run, as root, any commands it finds in /etc/ppp/ip-up whenever it activates a ppp/pppoe connection. Now anytime anyone on your computer activates the adsl connection, the mtu will be set to the correct value.

For the masochists, type "man pppd" in a terminal window for more info about this and other cool features of the ppp daemon.

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Permanent mtu adjustment
Authored by: haya785 on Nov 14, '01 11:36:19PM

I need to get a permanent mtu adjustment but for my ethernet connections... right now i have to enter:
sudo /sbin/ifconfig en1 mtu 1492
sudo /sbin/ifconfig en0 mtu 1492

everytime i restar my computer... If anyone knows how to do this plzzzzzzzzzzzzz let me know



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StartupItem
Authored by: Moo0 on Mar 23, '02 11:01:15AM

create a starup item; check /Library/StartupItems, where you'll most likely find an example of how to make on of those.



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Permanent mtu adjustment
Authored by: Alan Nursall on Mar 23, '02 09:37:57AM

Hallelujah! I have spent six months trying to get all my Macs at home to connect properly over DSL. I have no problem through the network at work.

At home, I was connected, assigned an IP address, and could ping other sites. But I could not make a browser or mail application actually do anything. The only site I could get any sort of access to was apple.com, and even then it was only the text. Images would not load. Couldn't even load a simple page like Google. It was like there was some sort of severe constriction in the pipeline. I used the advice from the message above and it worked!!

After experimenting with Ping, i set the mtu value at 1450 (1492 was too high and no packets were returned). For me anyway, this was ths solution after 6 months of struggle and swearing.

THANK YOU from Sudbury, Ontario!!!!



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Permanent mtu adjustment
Authored by: institute3 on Jun 26, '02 04:59:47PM

Posted by Institute3 (Bob Hager)
Is the procedure that you outlined also applicable to an ethernet
link? I have my powermac G4 933 networked with my PC running XP using
ICS. Connection is via a linksys card in the PC and a crossover RJ45
cable..

My broadband connection to the internet is via DirecPC (one way). Not able
to get DSL or cable where I live.

Recently upgraded to version 10.1.5 on the MAC..

Tried to modify the MTU via the terminal app but Darwin would not let me do the
update... permission denied.. and I logged in as system administrator..

This is the procedure that I used:

MTU
1) Start Terminal.app
2) sudo (login as rootuser)
3) type "ifconfig en0 mtu 1460" for your hardwired ethernet port and type "ifconfig en1 mtu 1460" for your airport connection if utilizing this one
4) now its time for the kernel extensions...

Kernel Extensions
1) Start Terminal.app (if you closed it between steps"
2) sudo (login as rootuser if you closed the above session)
3) type the following
sysctl -w net.inet.tcp.rcvspace=224360
sysctl -w net.inet.tcp.delayed_ack=1
4) that's it quit the terminal.app and enjoy faster downloads.

Downside to this is, you have to type this each time you reboot the machine.

I suspect that I was doing something wrong when logging in as the root user. Must say that is am a babe in the woods when it comes to UNIX.

Thanks much for any assistance that you can provide...



[ Reply to This | # ]
Permanent mtu adjustment
Authored by: institute3 on Jun 26, '02 05:02:46PM

Posted by Institute3 (Bob Hager)
Is the procedure that you outlined also applicable to an ethernet
link? I have my powermac G4 933 networked with my PC running XP using
ICS. Connection is via a linksys card in the PC and a crossover RJ45
cable..

My broadband connection to the internet is via DirecPC (one way). Not able
to get DSL or cable where I live.

Recently upgraded to version 10.1.5 on the MAC..

Tried to modify the MTU via the terminal app but Darwin would not let me do the
update... permission denied.. and I logged in as system administrator..

This is the procedure that I used:

MTU
1) Start Terminal.app
2) sudo (login as rootuser)
3) type "ifconfig en0 mtu 1460" for your hardwired ethernet port and type "ifconfig en1 mtu 1460" for your airport connection if utilizing this one
4) now its time for the kernel extensions...

Kernel Extensions
1) Start Terminal.app (if you closed it between steps"
2) sudo (login as rootuser if you closed the above session)
3) type the following
sysctl -w net.inet.tcp.rcvspace=224360
sysctl -w net.inet.tcp.delayed_ack=1
4) that's it quit the terminal.app and enjoy faster downloads.

Downside to this is, you have to type this each time you reboot the machine.

I suspect that I was doing something wrong when logging in as the root user. Must say that is am a babe in the woods when it comes to UNIX.

Thanks much for any assistance that you can provide...



[ Reply to This | # ]