PMG 6 message size limit problem

hata_ph

Well-Known Member
Nov 13, 2019
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Currently using pmg 6.0-4 as incoming and outgoing mail gateway, notice the message_size_limit setting is not working.
I have set a 15MB message size limit but when I try to send a 10MB mail, I received bounce back email saying "552 5.3.4 Message size exceeds fixed limit".
If i bypass the pmg and send directly using my mail server, no problem sending out the 10mb mail.
If i change the message_size_limit to 40mb, i can send out the 10mb email.
May I know is there any changes to pmg 6 as i have no problem using the same setting on pmg 5.

PS: mail.xxx.local (192.168.40.230) is my local mail server.

Nov 13 14:18:11 pmg postfix/qmgr[7154]: B7430412BC: removed
Nov 13 14:18:12 pmg postfix/smtp[9753]: connect to aspmx.l.google.com[2404:6800:4003:c03::1a]:25: Network is unreachable
Nov 13 14:18:15 pmg postfix/smtpd[9782]: connect from mail.xxx.local[192.168.40.230]
Nov 13 14:18:15 pmg postfix/smtpd[9782]: NOQUEUE: reject: MAIL from mail.xxx.local[192.168.40.230]: 552 5.3.4 Message size exceeds fixed limit; from=<xxx@xxx.local> proto=ESMTP helo=<mail.xxx.local>
Nov 13 14:18:15 pmg postfix/smtpd[9782]: disconnect from mail.eadeco.com.my[192.168.40.230] ehlo=1 mail=0/1 quit=1 commands=2/3
Nov 13 14:18:17 pmg postfix/smtp[9615]: A2C02410CB: to=<jeremy@xxx.hk>, relay=aspmx.l.google.com[74.125.68.27]:25, delay=5.9, delays=0.07/0/0.79/5.1, dsn=2.0.0, status=sent (250 2.0.0 OK 1573625897 w16si1516784pff.26 - gsmtp)
Nov 13 14:18:17 pmg postfix/qmgr[7154]: A2C02410CB: removed
Nov 13 14:18:18 pmg postfix/smtp[9753]: A480741177: to=<clarisse@xxx.com>, relay=aspmx.l.google.com[74.125.68.27]:25, delay=6.4, delays=0.07/0/1.3/5, dsn=2.0.0, status=sent (250 2.0.0 OK 1573625897 d4si1473519pgm.573 - gsmtp)
Nov 13 14:18:18 pmg postfix/qmgr[7154]: A480741177: removed
Nov 13 14:18:18 pmg postfix/qmgr[7154]: 7F4764129B: from=<xxx@xxx.local>, size=446976, nrcpt=1 (queue active)

root@pmg:~# postconf | grep size
berkeley_db_create_buffer_size = 16777216
berkeley_db_read_buffer_size = 131072
body_checks_size_limit = 51200
bounce_size_limit = 50000
header_size_limit = 102400
lmdb_map_size = 16777216
mailbox_size_limit = 51200000
message_size_limit = 15728640
tcp_windowsize = 0
 
Currently using pmg 6.0-4 as incoming and outgoing mail gateway, notice the message_size_limit setting is not working.
I have set a 15MB message size limit but when I try to send a 10MB mail, I received bounce back email saying "552 5.3.4 Message size exceeds fixed limit".
If i bypass the pmg and send directly using my mail server, no problem sending out the 10mb mail.
If i change the message_size_limit to 40mb, i can send out the 10mb email.
May I know is there any changes to pmg 6 as i have no problem using the same setting on pmg 5.

PS: mail.xxx.local (192.168.40.230) is my local mail server.

Nov 13 14:18:11 pmg postfix/qmgr[7154]: B7430412BC: removed
Nov 13 14:18:12 pmg postfix/smtp[9753]: connect to aspmx.l.google.com[2404:6800:4003:c03::1a]:25: Network is unreachable
Nov 13 14:18:15 pmg postfix/smtpd[9782]: connect from mail.xxx.local[192.168.40.230]
Nov 13 14:18:15 pmg postfix/smtpd[9782]: NOQUEUE: reject: MAIL from mail.xxx.local[192.168.40.230]: 552 5.3.4 Message size exceeds fixed limit; from=<xxx@xxx.local> proto=ESMTP helo=<mail.xxx.local>
Nov 13 14:18:15 pmg postfix/smtpd[9782]: disconnect from mail.eadeco.com.my[192.168.40.230] ehlo=1 mail=0/1 quit=1 commands=2/3
Nov 13 14:18:17 pmg postfix/smtp[9615]: A2C02410CB: to=<jeremy@xxx.hk>, relay=aspmx.l.google.com[74.125.68.27]:25, delay=5.9, delays=0.07/0/0.79/5.1, dsn=2.0.0, status=sent (250 2.0.0 OK 1573625897 w16si1516784pff.26 - gsmtp)
Nov 13 14:18:17 pmg postfix/qmgr[7154]: A2C02410CB: removed
Nov 13 14:18:18 pmg postfix/smtp[9753]: A480741177: to=<clarisse@xxx.com>, relay=aspmx.l.google.com[74.125.68.27]:25, delay=6.4, delays=0.07/0/1.3/5, dsn=2.0.0, status=sent (250 2.0.0 OK 1573625897 d4si1473519pgm.573 - gsmtp)
Nov 13 14:18:18 pmg postfix/qmgr[7154]: A480741177: removed
Nov 13 14:18:18 pmg postfix/qmgr[7154]: 7F4764129B: from=<xxx@xxx.local>, size=446976, nrcpt=1 (queue active)

root@pmg:~# postconf | grep size
berkeley_db_create_buffer_size = 16777216
berkeley_db_read_buffer_size = 131072
body_checks_size_limit = 51200
bounce_size_limit = 50000
header_size_limit = 102400
lmdb_map_size = 16777216
mailbox_size_limit = 51200000
message_size_limit = 15728640
tcp_windowsize = 0


You need at least 2.5 times the size of message_size_limit as it will include headers+envelops such metadatas.So for 12 MB limit I set 25 MB size and its working as required.
 
@ithelpdesk, I set 30MB message size limit, still cannot send out a 10MB email.
To set a 10MB message size limit, I need to set 35MB in postconf.
Btw, the same 15MB setting work on PMG 5. Is there a new settings?
 
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@hata_ph - that seems odd - could you please post the complete log (anonymize addresses and ips) of the successful delivery when setting the size to 35 M - the log should contain the size configured.
I assume you did not manually modify the postfix configuration templates?
 
No custom postfix config templates.
I am using groupwise as my local mail server, when I try to send a 10MB email to gmail going throught PMG 6 as my outgoing mail gateway, I notice the size have become 32716584 while in the groupwise client just show 10486201.
Could it be PMG adding more data to the email?

Capture.JPG

Code:
Nov 14 09:15:39 pmg postfix/smtpd[17757]: connect from gw.xxx.local[192.168.40.230]
Nov 14 09:15:39 pmg postfix/smtpd[17757]: A9E0F413B2: client=gw.xxx.local[192.168.40.230]
Nov 14 09:15:39 pmg postfix/cleanup[15827]: A9E0F413B2: message-id=<5DCD1B2F020000F80011EA62@mail.xxx.local>
Nov 14 09:15:41 pmg postfix/qmgr[869]: A9E0F413B2: from=<lee@xxx.local>, size=32716584, nrcpt=1 (queue active)
Nov 14 09:15:41 pmg postfix/smtpd[17757]: disconnect from gw.xxx.local[192.168.40.230] ehlo=1 mail=1 rcpt=1 data=1 quit=1 commands=5
Nov 14 09:15:42 pmg pmg-smtp-filter[16930]: 413DA5DCCAABD6885F: new mail message-id=<5DCD1B2F020000F80011EA62@mail.xxx.local>#012
Nov 14 09:15:46 pmg pmg-smtp-filter[16930]: 413DA5DCCAABD6885F: SA score=0/5 time=3.897 bayes=0.00 autolearn=ham autolearn_force=no hits=ALL_TRUSTED(-1),AWL(0.124),BAYES_00(-1.9),TVD_SPACE_RATIO(0.001)
Nov 14 09:15:47 pmg pmg-smtp-filter[16930]: 413DA5DCCAABD6885F: accept mail to <xxx@gmail.com> (54FF2413F2) (rule: default-accept)
Nov 14 09:15:47 pmg pmg-smtp-filter[16930]: 413DA5DCCAABD6885F: processing time: 5.668 seconds (3.897, 0.009, 0)
Nov 14 09:15:47 pmg postfix/lmtp[15542]: A9E0F413B2: to=<xxx@gmail.com>, relay=127.0.0.1[127.0.0.1]:10023, delay=7.7, delays=1.7/0/0.04/6, dsn=2.5.0, status=sent (250 2.5.0 OK (413DA5DCCAABD6885F))
Nov 14 09:15:47 pmg postfix/qmgr[869]: A9E0F413B2: removed
 
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I have try setup another postfix relay with my local groupwise mail server, same problem. A 10MB email will show around 31MB in postfix.
When I try to use thunderbird client, postfix see the mail around 14MB which is reasonable.
Then I suspect the groupwise client is add more data to all the outgoing mail, i try disable the global banner/disclaimer still the size is big.
Unless I can find out what is going on with the groupwise client then my only option is to set message_size_limit = 35MB. o_O