Testing a null modem serial connection under linux

Used this to test the connectivity of two HA-Nodes connected via a null modem cable on their serial ports. Also nice to find which ports are connected, since not every machine has their ports mapped to the same devices…
clipped from www.ibm.com
Set up the serial connection
Use a null modem cable to connect the two nodes through their serial ports. Now test the serial connection, as follows:
On ha1 (receiver), type:

cat < /dev/ttyS0

On ha2 (sender) type:

echo "Serial Connection test" > /dev/ttyS0

You should see the text on the receiver node (ha1). If it works, change their roles and try again.

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