sendmail, 4th Edition

MAX...

Redefine maximums Port, edit specific files

When porting sendmail to a new system or tuning it for special needs, you might need to adjust one of sendmail’s predefined maximums. These cannot be tuned in your Build m4 file. Instead, each needs to be changed in the file indicated by the third column of Table 3-7. In general, maximums should never be changed in either direction without first examining the code for possible side effects. Check to see if any minimums are required or if any warnings about maximums are evident in the code or in a README file. Some of these limits are defined by RFC, and should not be changed from the standard set by the appropriate RFC.

Table 3-7. Compile-time macros to redefine maximums

Compile-time macro	Default	File	Maximum
[a]
DEFAULT_MAX_RCPT	100	sendmail/conf.h	Initial max RCPTs per envelope (V8.12 and above)
ENHSCLEN	10	sendmail/conf.h	Length of enhanced status code[a]
MACBUFSIZE	4096	sendmail/conf.h	Expansion of a defined macro
MAXALIASDB	12	sendmail/conf.h	Number of alias databases
MAXATOM	200	sendmail/conf.h	Atoms (tokens) in an address
MAXBADCOMMANDS	25	sendmail/srvrsmtp.c	Bad SMTP commands (V8.12 and above)
MAXDAEMONS	10	sendmail/conf.h	Ports on which to listen
MAXDNSRCH	6	sendmail/domain.c	Possible domains to search
MAXETRNCOMMANDS	8	sendmail/srvrsmtp.c	ETRNs before slowdown (V8.12 and above)
MAXFILTERMACROS	50	sendmail/conf.h	Macros per Milter command (V8.12 and above)
MAXFILTERS	25	sendmail/conf.h ...