abnormal endings - a feature-free blog for jwaabnormal endings - it's the DS-3, not me.


avr counter fun
wiggle room
pineapple upside-down cake
restting the counter
it's frickin' hot in here, mr. bigglesworth.
five by five
my first parallel port project
DS-3 asynchronously
new glasses
it's the DS-3, not me.
SAP, DS-3, you, and me.

it's the DS-3, not me.

@ Sun Mar 6 20:42:19 PST 2006
tagged with work network

The DS-3 can't pass zeroes. Why? Who knows.

This evening I had the circuit provider engineer route traffic from my Linux desktop across the DS-3. I used the perl doodad to generate the problematic SAP traffic from my desktop, and wrote another perl doodad to echo the traffic back to me. In essence it was a ping; send data to the server, and the server sends it right back 'atcha.

The ping failed. Failed! This means the problem isn't in the SAP server (hooray; troubleshooting that would have sucked bigtime.) I start chopping the packet down, trying to figure out which sequence of bytes are not passing. Finally, I am left with about 96 nulls. They don't pass. I mention this to the engineer. He says "Huh! that sounds familiar!" and a few seconds later says "I'm able to confirm this." He used ping on one of the routers to send a few dozen null bytes to the other router, and confirms they don't pass. I play with 'ping -p' from my Linux machine and confirm as well. Hooray! Now that the circuit provider can replicate the problem, we can stop pointing fingers and get things going.