RCF 5321 says:
4.5.3.1.1. Local-part
The maximum total length of a user name or other local-part is 64
octets.
RFC 2821 says:
local-part
The maximum total length of a user name or other local-part is 64 characters.
RFC 821 says:
user
The maximum total length of a user name is 64 characters.
When I fed my postfix-2.8-20101108 (I'm using strict_rfc821_envelopes = yes)
with this:
# telnet localhost 10026
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 mail.charite.de ESMTP
EHLO foo
250-mail.charite.de
250-PIPELINING
250-SIZE 26214400
250-ETRN
250-STARTTLS
250-XFORWARD NAME ADDR PROTO HELO SOURCE PORT IDENT
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
MAIL FROM:<>
250 2.1.0 Ok
RCPT
TO:<0123456789012345678901234567890123456789012345678901234567890123456...@example.com>
250 2.1.5 Ok
RCPT
TO:<0123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456...@example.com>
250 2.1.5 Ok
QUIT
221 2.0.0 Bye
Connection closed by foreign host.
I received no error message; but when using a domain literal
exceeeding 63 characters I received an error.
On second thought, VERP is "encoding" the whole recipient address into
the local part (of the sender address) when sending out mail; thus
restricting the localpart to 64 characters would make little sense.
But where IS the actual limit in postfix?
max_line_lenght - lenght(RCPT TO:<>) ?
--
Ralf Hildebrandt
Geschäftsbereich IT | Abteilung Netzwerk
Charité - Universitätsmedizin Berlin
Campus Benjamin Franklin
Hindenburgdamm 30 | D-12203 Berlin
Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
ralf.hildebra...@charite.de | http://www.charite.de
