Zimbra: Client Host Rejected

[leebrent]

Hello,

I have the following version of Zimbra running on FC7:
zcs-5.0.6_GA_2313.F7.20080522100316

I run a DNS test on my domain itas.ca at the following URL:

DNS Quick Check - DNS Report Tool, Test your DNS delegation, DNS Servers, Mail and Web Servers, Network Admins, Webmasters, Hosting

And the mail error that I am getting has my attention:

<<< 220 mail.itas.ca ESMTP Postfix
>>> HELO DNS Quick Check - DNS Report Tool, Test your DNS delegation, DNS Servers, Mail and Web Servers, Network Admins, Webmasters, Hosting
<<< 250 mail.itas.ca
>>> MAIL FROM: <dnscheck@uniplace.com>
<<< 250 2.1.0 Ok
>>> RCPT TO: <postmaster@itas.ca>
<<< 450 4.7.1 Client host rejected: cannot find your hostname, [195.60.98.252]
>>> RCPT TO: <root@itas.ca>
<<< 450 4.7.1 Client host rejected: cannot find your hostname, [195.60.98.252]
>>> RCPT TO: <info@itas.ca>
<<< 450 4.7.1 Client host rejected: cannot find your hostname, [195.60.98.252]
>>> RCPT TO: <webmaster@itas.ca>
<<< 550 5.1.1 <webmaster@itas.ca>: Recipient address rejected: itas.ca
Probably mail server does not accept mail for itas.ca (received status 550)

I was under the impression that all inbound mail was getting to this server until a user indicated that one of her friends was getting a bounce when emailing her.

The information that I have from the bounce is as follows:

Diagnostic-Code: X-BorderWare-Security-Platform; host
mail.itas.ca[142.25.97.202] said: 450 4.7.1 <MXOttawa.csc-scc.gc.ca>: Helo
command rejected: Host not found (in reply to RCPT TO command)
Will-Retry-Until: Mon, 2 Jun 2008 20:49:37 -0400 (EDT)

I have tired turning off the following, and still receive this error:

Hostname in greeting violates RFC (reject_invalid_hostname)
Client must greet with a fully qualified hostname (reject_non_fqdn_hostname)
Client's IP address (reject_unknown_client)
Hostname in greeting (reject_unknown_hostname)
Sender's domain (reject_unknown_sender_domain)'

Can someone offer me a solution for this problem, and possibly a way to test it without having to contact the user from csc-scc.gc.ca?

[phoenix]

Is this a new install or has the server been working for a while? Is it behind a NAT router or firewall? Run the following (on the zimbra server):

cat /etc/hosts 
host `hostname`  <-- type as-is and use backticks not single quotes
dig yourdomain.com mx
dig yourdomain.com any

and post the results.

[leebrent]

[root@mail zcs-5.0.6_GA_2313.F7.20080522100316]# cat /etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1       localhost.localdomain   localhost
::1     localhost6.localdomain6 localhost6
142.25.97.202   mail.itas.ca    mail

[root@mail zcs-5.0.6_GA_2313.F7.20080522100316]# host `hostname`
mail.itas.ca has address 142.25.97.202

[root@mail zcs-5.0.6_GA_2313.F7.20080522100316]# dig itas.ca mx

; <<>> DiG 9.4.2 <<>> itas.ca mx
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55838
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; QUESTION SECTION:
;itas.ca.                       IN      MX

;; ANSWER SECTION:
itas.ca.                3600    IN      MX      100 mail.itas.ca.

;; ADDITIONAL SECTION:
mail.itas.ca.           3600    IN      A       142.25.97.202

;; Query time: 3 msec
;; SERVER: 142.25.115.1#53(142.25.115.1)
;; WHEN: Thu May 29 09:05:33 2008
;; MSG SIZE  rcvd: 62

[root@mail zcs-5.0.6_GA_2313.F7.20080522100316]# dig itas.ca any

; <<>> DiG 9.4.2 <<>> itas.ca any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29732
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 7, AUTHORITY: 0, ADDITIONAL: 4

;; QUESTION SECTION:
;itas.ca.                       IN      ANY

;; ANSWER SECTION:
itas.ca.                3600    IN      A       142.25.97.200
itas.ca.                3600    IN      NS      titan.itas.ca.
itas.ca.                3600    IN      NS      quadra.mala.bc.ca.
itas.ca.                3600    IN      NS      triangle.mala.bc.ca.
itas.ca.                3600    IN      SOA     titan.itas.ca. mail.itas.ca. 200
8052902 3600 3600 604800 86400
itas.ca.                3600    IN      MX      100 mail.itas.ca.
itas.ca.                3600    IN      TXT     "v=spf1 mx ptr a:zimbra.itas.ca.
 a:titan.itas.ca. a:europa.itas.ca. a:callisto.itas.ca. a:help.itas.ca. a:pan.it
as.ca. a:mail.itas.ca. include:mala.bc.ca include:europa.itas.ca. include:titan.
itas.ca. include:callisto.itas.ca. include:pan.itas.ca. ~all"

;; ADDITIONAL SECTION:
titan.itas.ca.          3600    IN      A       142.25.97.200
quadra.mala.bc.ca.      43200   IN      A       142.25.115.12
triangle.mala.bc.ca.    43200   IN      A       142.25.115.1
mail.itas.ca.           3600    IN      A       142.25.97.202

;; Query time: 4 msec
;; SERVER: 142.25.115.1#53(142.25.115.1)
;; WHEN: Thu May 29 09:05:53 2008
;; MSG SIZE  rcvd: 498

[root@mail zcs-5.0.6_GA_2313.F7.20080522100316]#

[phoenix]

Is the only reason (apart from the bounced message) you think this is not working is because of the results of your DNS tests earlier? I have just done the same test on your server and the results were OK.

I'd suggest you check in the log files and see what errors are there and what reason was given for the bounce you mentioned earlier.

[leebrent]

This is what I found in the logs... The odd thing is that this person can email hotmail, but the mail does not make it to my server...

TP helo=<MXOttawa.csc-scc.gc.ca>
May 29 10:34:40 mail postfix/smtpd[29169]: NOQUEUE: reject: RCPT from mail.csc-s
cc.gc.ca[198.103.109.161]: 450 4.7.1 <MXOttawa.csc-scc.gc.ca>: Helo command reje
cted: Host not found; from=<HeadDA@CSC-SCC.GC.CA> to=<betheak@itas.ca> proto=ESM
TP helo=<MXOttawa.csc-scc.gc.ca>