Oracle Message PGA-21450 - communication error: string failed, errno = number

ERROR	communication error: string failed, errno = number
CAUSE	The AIX SNA function failed with a system error number of .
ACTION	The AIX SNA error codes are documented in the IBM manual AIX SNA Server: Diagnosis Guide and Messages. Use this manual to determine the cause of the problem and correct it. AIX SNA system error numbers are also documented in the /usr/include/luxsna.h header file on AIX systems.