How to run a tcpdump on the HMC

How to run tcpdump on HMC for network/rmc troubleshooting:

Login to HMC as hscpe, pesh to root.

on HMC:
tcpdump -i (public interface) -w /dump/tcpdump.bin -s 1500 port 657

on LPAR:
Use the same syntax but use the interface that has an IP on the same subnet as HMC’s public interface.

tcpdump -i ent0 or ent1 -w /tmp/tcpdump.lpar.bin -s 1500 port 657

Then login again to lpar on a second session:

run /usr/sbin/rsct/install/bin/recfgct

Wait 2-4 minutes.

/usr/sbin/rsct/bin/rmcctrl -z
/usr/sbin/rsct/bin/rmcctrl -A
/usr/sbin/rsct/bin/rmcctrl -p

From lpar:
ping <hmc_public_ip>

Control c to stop tcpdump on both lpar and on the HMC.

Trace information will be found in the files specified by -w flag and can be used for problem analysis .