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BSWMEZ-3548pwr-a(config)#logging ?
Hostname or A.B.C.D IP address of the logging host
buffered Set buffered logging parameters
cns-events Set CNS Event logging level
console Set console logging level
facility Facility parameter for syslog messages
file Set logging file parameters
history Configure syslog history table
monitor Set terminal line (monitor) logging level
on Enable logging to all supported destinations
source-interface Specify interface for source address in logging
transactions
trap Set syslog server logging level
So logging 12.13.14.15 would send syslog messages to 12.13.14.15.