Author: AlekZ

Jumbo frames on Cisco

For IOS:

3750(config)# system mtu jumbo 9000
3750(config)# exit
3750# reload

7609(config)#int gigabitEthernet 1/1
7609(config-if)#mtu ?
<1500-9216> MTU size in bytes

7609(config-if)#mtu 9216

Verify in Native IOS:

7609#show interfaces gigabitEthernet 1/1
GigabitEthernet1/1 is up, line protocol is up (connected)
Hardware is C6k 1000Mb 802.3, address is 0007.0d0e.640a (bia 0007.0d0e.640a)
MTU 9216 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255

For CatOS:

Cat6509> (enable) set port jumbo
Usage: set port jumbo <mod/port> <enable|disable>
Cat6509> (enable) set port jumbo 1/1 enable
Jumbo frames enabled on port 1/1.
Cat6509> (enable) 2002 May 29 12:34:35 %PAGP-5-PORTFROMSTP:
Port 1/1 left bridge port 1/1
2002 May 29 12:34:38 %PAGP-5-PORTTOSTP:Port 1/1 joined bridge port 1/1

Verify in CatOS

Cat6509> (enable) show port jumbo
Jumbo frames MTU size is 9216 bytes.
Jumbo frames enabled on port(s) 1/1,9/1.

Literature:
Cisco manual

Jumbo frames on Solaris

For e1000g (Solaris):
Change /kernel/drv/e1000g.conf to:

MaxFrameSize=3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3;
# 0 is for normal ethernet frames.
# 1 is for upto 4k size frames.
# 2 is for upto 8k size frames.
# 3 is for upto 16k size frames.
# These are maximum frame limits, not the actual ethernet frame
# size. Your actual ethernet frame size would be determined by
# protocol stack configuration (please refer to ndd command man pages)
# For Jumbo Frame Support (9k ethernet packet)
# use 3 (upto 16k size frames)

For rge (Solaris):
Maximum MTU supported by rge is 7000.
Change /kernel/drv/rge.conf to:

default_mtu = 7000;

Then reboot.

The result:

xeon# ifconfig -a
. . .
e1000g1: flags=201000843 mtu 9000 index 2
inet 10.0.10.1 netmask ffffff00 broadcast 10.0.10.255
ether 0:18:f3:ef:2a:d1

Finite Elemente – The Resonator

I’m a big fan of Finite Elemente creations. I had or still have Spider and Master Reference Pagode racks, Ceraballs, Cerapucs, Cerabases… All of them brought a great deal of enhancements in dynamics and resonance dumping. So I thought that The Resonator will definitely not hurt and hopefully bring me closer to There. The idea was to use it on top of the Transporter, which is known for its thin ringy tincan case. But considering the price (319-400EUR in Europe, $550-745 in the US) I decided to audition it first and borrowed one from my dealer.

From the description and ad campaigns:

  • Diameter: 120mm
  • Height: 30mm
  • Weight: 370g
  • Material: anodized aluminium (silver or black), stainless steel insert
  • The Resonator converts the resonance energy into heat across a broad band, instead of relocating its spectrum or generating new intrinsic like conventional attenuation of component cabinets, using mass blocks, for example.
  • Strategically placing the Resonator in a resonant zone on your component’s chassis, can reduce vibration by more than 20dB

This is what it looks like:

Continue reading “Finite Elemente – The Resonator”

How to change MTU (Windows)

Two possible scenarios:

  • You are using VPN, but some of your applications time out (MTU is too big)
  • Your OS is preconfigured for VPN by your employer, but the transfer rate can be better (MTU is too small)

In both cases the MTU needs to be adjusted:

  1. Start regedit
  2. Check all interfaces under HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces and find the one with the IP corresponding to the problem interface (e.g. the VPN tunnel interface). For example:
    IPAddress REG_MULTI_SZ 192.168.12.1
    MTU REG_DWORD 0x000005DC (1500)

    As you can see the MTU is set to 1500 what is too high for a VPN tunnel

  3. Double click on MTU
  4. Click on Decimal
  5. Enter 1400 (or 1300 to be on the safe side, or 1500 if you are not using VPN)
  6. Click OK
  7. Reconnect (if you are connected to the VPN)

Also see:

Windows 2000/XP Registry Tweaks
How to change the PPPoE MTU size in Windows XP
Change the Maximum Transmission Unit (MTU) Size (Windows NT/2000/XP)

External searching in mybb

Sometimes you need to integrate web-pages with corresponding forum threads. Here’s one of the ways to do it.

<?php
$keywords=”MyBB integration”; // The search keywords
?>
<!– The path to mybb search.php –>
<form method=”post” action=”http://www.yoursite.com/mybb/search.php”>
<input type=”hidden” name=”action” value=”do_search” />
<input type=”hidden” name=”keywords” value=”<?php echo $keywords; ?>” />
<!– search titles only –>
<input type=”hidden”  name=”postthread” value=”2″ />
<!– Search in all forums –>
<input type=”hidden” name=”forums[]” size=”15″ multiple=”multiple” value=”all”>
<!– All dates –>
<input type=”hidden” name=”postdate” value=”0″>
<input type=”hidden” name=”pddir” value=”1″ />
<input type=”hidden” name=”sortby” value=”lastpost”>
<input type=”hidden” name=”sortordr” value=”asc” />
<!– the result will be threads, not posts –>
<input type=”hidden” name=”showresults” value=”threads” />
<input type=”submit” class=”button” name=”submit” value=”Forum” />
</form>