How to Enable Ethernet Jumbo Frames on the PCI Gigabit Card

[MACAWI]

hello.

I would like to know how can we Enable Ethernet Jumbo Frames on the PCI Gigabit Card in Mac OS X Server 10.3, Xserve thanks for help

[RoninBlade]

Here you can follow the steps to solve to enable jumbo frame

Warnings:

1. All devices on a local network must be configured to use Jumbo Frames, or loss of connectivity could occur on that network.
   
2. All devices on the local network must support use of Jumbo Frames. Few network switches support Jumbo Frames, and sending them to a switch that does not support them may cause the switch to stop operating. Check the specifications of network hardware prior to enabling Jumbo Frames. Even if your devices are Jumbo Frame compatible, Jumbo Frames are not needed under most circumstances. Be sure you have a need for them before using this procedure.
   
3. This procedure is intended only for computers with Mac OS X Server and the PCI Gigabit Card, or for the Xserve G5. Jumbo Frames can be used on the built-in Ethernet port only on the Xserve G5.

Enabling Jumbo Frames
If you have Mac OS X Server 10.3 or later, you can set up Jumbo Frames via normal administration applications. The steps below would not be needed.

[RoninBlade]

If you have Mac OS X Server 10.2.4 to 10.2.8, follow these steps to create a script that is executed during startup:

1. Make sure you are logged in with an administrator account.
2. Open Terminal (/Applications/Utilities).
3. Type: mkdir -p /Library/StartupItems/JumboFrame
4. Press Return.
5. Type: cd /Library/StartupItems/JumboFrame
6. Press Return.
7. Type: pico JumboFrame
8. Press Return.
9. In the pico editor, paste in the following text.
   
   

   #!/bin/sh
   
   ##
   # Configure kernel parameters for Jumbo Frame support
   ##
   
   . /etc/rc.common
   
   StartService ()
   {
   ConsoleMessage "Configuring for Jumbo Frames"
   
   if [ "${JUMBOFRAME:=-NO-}" = "-YES-" ]; then
   
   /usr/sbin/sysctl -w net.inet.raw.maxdgram=16384
   /usr/sbin/sysctl -w net.inet.raw.recvspace=16384
   /usr/sbin/sysctl -w net.inet.tcp.sendspace=65536
   /usr/sbin/sysctl -w net.inet.tcp.recvspace=65536
   /usr/sbin/sysctl -w net.inet.udp.recvspace=65536
   
   fi
   
   }
   
   StopService ()
   {
   return 0
   }
   
   RestartService ()
   {
   return 0
   }
   
   RunService "$1"

10. Save the file (Control-O, Return), and exit pico (Control-X).
11. Type: chmod 755 JumboFrame
12. Press Return.
13. Type: pico StartupParameters.plist
14. Press Return.
15. Paste the following text into the pico editor:
    
    

    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN"
    "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
    <plist version="1.0">
    <dict>
    <key>Description</key>
    <string>Can set Jumbo Ethernet Frames</string>
    <key>OrderPreference</key>
    <string>None</string>
    <key>Provides</key>
    <array>
    <string>JumboFrame</string>
    </array>
    <key>Requires</key>
    <array>
    <string>Network Configuration</string>
    </array>
    </dict>
    </plist>

16. Save the file (Control-O, Return) and exit pico (Control-X).
17. Type: chmod 644 StartupParameters.plist
18. Press Return.
19. Type: sudo pico /etc/hostconfig
20. When prompted, enter your account password.
21. Press Return.
22. In the pico editor, add this line at the bottom (use the down arrow key to navigate to the file end):
    
    
    JUMBOFRAME=-YES-
    
    
23. Save it (Control-O, Return) and exit pico (Control-X).
    
    When you restart the computer, the script makes the kernel parameter settings necessary to support Ethernet Jumbo Frames. Once that is done, you can enable Jumbo Frames on the PCI Gigabit port using this command:
    
    
    sudo networksetup -setMTU en1 9000
    
    
    If your PCI Gigabit card has a port name different from "en1", you should change the port name in the command to match. Repeat this command if you have multiple PCI Gigabit cards, substituting the other port names.
    
    This setting is retained after a restart and does not need to be entered after each startup.