[ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- From: "Gabriel E. Rincon" <gerincon@xxxxxxxxxx>
- To: <exchangelist@xxxxxxxxxxxxx>
- Date: Sat, 20 Oct 2007 07:57:57 -0500
John,
Here is the DNS report for your domain thompsonig.com. Hopefully this will
help.
Category
Status
Test Name
Information
Parent
PASS
Missing Direct Parent check
OK. Your direct parent zone exists, which is good. Some domains (usually third
or fourth level domains, such as example.co.us) do not have a direct parent
zone ('co.us' in this example), which is legal but can cause confusion.
INFO
NS records at parent servers
Your NS records at the parent servers are:
ns1.acomhosting.com. [69.25.72.105] [TTL=172800] [US]
ns2.acomhosting.com. [69.25.72.106] [TTL=172800] [US]
[These were obtained from h.gtld-servers.net]
PASS
Parent nameservers have your nameservers listed
OK. When someone uses DNS to look up your domain, the first step (if it doesn't
already know about your domain) is to go to the parent servers. If you aren't
listed there, you can't be found. But you are listed there.
PASS
Glue at parent nameservers
OK. The parent servers have glue for your nameservers. That means they send out
the IP address of your nameservers, as well as their host names.
PASS
DNS servers have A records
OK. All your DNS servers either have A records at the zone parent servers, or
do not need them (if the DNS servers are on other TLDs). A records are required
for your hostnames to ensure that other DNS servers can reach your DNS servers.
Note that there will be problems if your DNS servers do not have these same A
records.
NS
INFO
NS records at your nameservers
Your NS records at your nameservers are:
ns1.acomhosting.com. [69.25.72.105] [TTL=86400]
ns2.acomhosting.com. [69.25.72.106] [TTL=86400]
FAIL
Open DNS servers
ERROR: One or more of your nameservers reports that it is an open DNS server.
This usually means that anyone in the world can query it for domains it is not
authoritative for (it is possible that the DNS server advertises that it does
recursive lookups when it does not, but that shouldn't happen). This can cause
an excessive load on your DNS server. Also, it is strongly discouraged to have
a DNS server be both authoritative for your domain and be recursive (even if it
is not open), due to the potential for cache poisoning (with no recursion,
there is no cache, and it is impossible to poison it). Also, the bad guys could
use your DNS server as part of an attack, by forging their IP address. Problem
record(s) are:
Server 69.25.72.105 reports that it will do recursive lookups. [test
<http://www.dnsstuff.com/tools/lookup.ch?domain=www.DNSstuff.com&server=69.25.72.105>
] Server 69.25.72.106 reports that it will do recursive lookups. [test
<http://www.dnsstuff.com/tools/lookup.ch?domain=www.DNSstuff.com&server=69.25.72.106>
] See this page <http://member.dnsstuff.com/info/opendns.php> for info on
closing open DNS servers.
PASS
Mismatched glue
OK. The DNS report did not detect any discrepancies between the glue provided
by the parent servers and that provided by your authoritative DNS servers.
PASS
No NS A records at nameservers
OK. Your nameservers do include corresponding A records when asked for your NS
records. This ensures that your DNS servers know the A records corresponding to
all your NS records.
PASS
All nameservers report identical NS records
OK. The NS records at all your nameservers are identical.
PASS
All nameservers respond
OK. All of your nameservers listed at the parent nameservers responded.
PASS
Nameserver name validity
OK. All of the NS records that your nameservers report seem valid (no IPs or
partial domain names).
PASS
Number of nameservers
OK. You have 2 nameservers. You must have at least 2 nameservers (RFC2182
<http://www.DNSstuff.com/pages/rfc2182.htm> section 5 recommends at least 3
nameservers), and preferably no more than 7.
PASS
Lame nameservers
OK. All the nameservers listed at the parent servers answer authoritatively for
your domain.
PASS
Missing (stealth) nameservers
OK. All 2 of your nameservers (as reported by your nameservers) are also listed
at the parent servers.
PASS
Missing nameservers 2
OK. All of the nameservers listed at the parent nameservers are also listed as
NS records at your nameservers.
PASS
No CNAMEs for domain
OK. There are no CNAMEs for thompsonig.com. RFC1912
<http://www.DNSstuff.com/pages/rfc1912.htm> 2.4 and RFC2181
<http://www.dnsstuff.com/tools/rfc.ch?detail=2181> 10.3 state that there
should be no CNAMEs if an NS (or any other) record is present.
PASS
No NSs with CNAMEs
OK. There are no CNAMEs for your NS records. RFC1912
<http://www.DNSstuff.com/pages/rfc1912.htm> 2.4 and RFC2181
<http://www.dnsstuff.com/tools/rfc.ch?detail=2181> 10.3 state that there
should be no CNAMEs if an NS (or any other) record is present.
WARN
Nameservers on separate class C's
WARNING: All of your nameservers (listed at the parent nameservers) are in the
same Class C (technically, /24) address space, which means that they are
probably at the same physical location. Your nameservers should be at
geographically dispersed locations. You should not have all of your nameservers
at the same location. RFC2182 <http://www.DNSstuff.com/pages/rfc2182.htm> 3.1
goes into more detail about secondary nameserver location.
PASS
All NS IPs public
OK. All of your NS records appear to use public IPs. If there were any private
IPs, they would not be reachable, causing DNS delays.
PASS
TCP Allowed
OK. All your DNS servers allow TCP connections. Although rarely used, TCP
connections are occasionally used instead of UDP connections. When firewalls
block the TCP DNS connections, it can cause hard-to-diagnose problems.
WARN
Single Point of Failure
WARNING: Although you have at least 2 NS records, they may both point to the
same server (one of our two tests shows them being the same, the other does
not), which would result in a single point of failure. You are required to have
at least 2 nameservers per RFC 1035 <http://www.DNSstuff.com/pages/rfc1035.htm>
section 2.2.
INFO
Nameservers versions
[For security reasons, this test is limited to members]
PASS
Stealth NS record leakage
Your DNS servers do not leak any stealth NS records (if any) in non-NS requests.
SOA
INFO
SOA record
Your SOA record [TTL=86400] is:
Primary nameserver: ns1.acomhosting.com.
Hostmaster E-mail address: service.acomhosting.com.
Serial #: 2005011497
Refresh: 10800
Retry: 3600
Expire: 604800
Default TTL: 86400
PASS
NS agreement on SOA serial #
OK. All your nameservers agree that your SOA serial number is 2005011497. That
means that all your nameservers are using the same data (unless you have
different sets of data with the same serial number, which would be very bad)!
Note that the DNSreport only checks the NS records listed at the parent servers
(not any stealth servers).
PASS
SOA MNAME Check
OK. Your SOA (Start of Authority) record states that your master (primary) name
server is: ns1.acomhosting.com.. That server is listed at the parent servers,
which is correct.
PASS
SOA RNAME Check
OK. Your SOA (Start of Authority) record states that your DNS contact E-mail
address is: service@xxxxxxxxxxxxxxxx (techie note: we have changed the initial
'.' to an '@' for display purposes).
PASS
SOA Serial Number
OK. Your SOA serial number is: 2005011497. This appears to be in the
recommended format of YYYYMMDDnn, where 'nn' is the revision. So this indicates
that your DNS was last updated on 14 Jan 2005 (and was revision #97). This
number must be incremented every time you make a DNS change.
PASS
SOA REFRESH value
OK. Your SOA REFRESH interval is : 10800 seconds. This seems normal (about
3600-7200 seconds is good if not using DNS NOTIFY; RFC1912
<http://www.DNSstuff.com/pages/rfc1912.htm> 2.2 recommends a value between
1200 to 43200 seconds (20 minutes to 12 hours)). This value determines how
often secondary/slave nameservers check with the master for updates.
PASS
SOA RETRY value
OK. Your SOA RETRY interval is : 3600 seconds. This seems normal (about
120-7200 seconds is good). The retry value is the amount of time your
secondary/slave nameservers will wait to contact the master nameserver again if
the last attempt failed.
PASS
SOA EXPIRE value
OK. Your SOA EXPIRE time: 604800 seconds. This seems normal (about 1209600 to
2419200 seconds (2-4 weeks) is good). RFC1912
<http://www.DNSstuff.com/pages/rfc1912.htm> suggests 2-4 weeks. This is how
long a secondary/slave nameserver will wait before considering its DNS data
stale if it can't reach the primary nameserver.
PASS
SOA MINIMUM TTL value
OK. Your SOA MINIMUM TTL is: 86400 seconds. This seems normal (about 3,600 to
86400 seconds or 1-24 hours is good). RFC2308
<http://www.DNSstuff.com/pages/rfc2308.htm> suggests a value of 1-3 hours.
This value used to determine the default (technically, minimum) TTL
(time-to-live) for DNS entries, but now is used for negative caching.
MX
INFO
MX Record
Your 1 MX record is:
5 exchangesrvr.thompsonig.com. [TTL=86400] IP=67.108.89.73 [TTL=86400] [US]
PASS
Low port test
OK. Our local DNS server that uses a low port number can get your MX record.
Some DNS servers are behind firewalls that block low port numbers. This does
not guarantee that your DNS server does not block low ports (this specific
lookup must be cached), but is a good indication that it does not.
PASS
Invalid characters
OK. All of your MX records appear to use valid hostnames, without any invalid
characters.
PASS
All MX IPs public
OK. All of your MX records appear to use public IPs. If there were any private
IPs, they would not be reachable, causing slight mail delays, extra resource
usage, and possibly bounced mail.
PASS
MX records are not CNAMEs
OK. Looking up your MX record did not just return a CNAME. If an MX record
query returns a CNAME, extra processing is required, and some mail servers may
not be able to handle it.
PASS
MX A lookups have no CNAMEs
OK. There appear to be no CNAMEs returned for A records lookups from your MX
records (CNAMEs are prohibited in MX records, according to RFC974
<http://www.DNSstuff.com/pages/rfc974.htm> , RFC1034
<http://www.dnsstuff.com/tools/rfc.ch?detail=1034> 3.6.2, RFC1912
<http://www.dnsstuff.com/tools/rfc.ch?detail=1912> 2.4, and RFC2181
<http://www.dnsstuff.com/tools/rfc.ch?detail=2181> 10.3).
PASS
MX is host name, not IP
OK. All of your MX records are host names (as opposed to IP addresses, which
are not allowed in MX records).
INFO
Multiple MX records
NOTE: You only have 1 MX record. If your primary mail server is down or
unreachable, there is a chance that mail may have troubles reaching you. In the
past, mailservers would usually re-try E-mail for up to 48 hours. But many now
only re-try for a couple of hours. If your primary mailserver is very reliable
(or can be fixed quickly if it goes down), having just one mailserver may be
acceptable.
PASS
Differing MX-A records
OK. I did not detect differing IPs for your MX records (this would happen if
your DNS servers return different IPs than the DNS servers that are
authoritative for the hostname in your MX records).
PASS
Duplicate MX records
OK. You do not have any duplicate MX records (pointing to the same IP).
Although technically valid, duplicate MX records can cause a lot of confusion,
and waste resources.
PASS
Reverse DNS entries for MX records
OK. The IPs of all of your mail server(s) have reverse DNS (PTR) entries.
RFC1912 <http://www.DNSstuff.com/pages/rfc1912.htm> 2.1 says you should have a
reverse DNS for all your mail servers. It is strongly urged that you have them,
as many mailservers will not accept mail from mailservers with no reverse DNS
entry. Note that this information is cached, so if you changed it recently, it
will not be reflected here (see the www.DNSstuff.com Reverse DNS Tool
<http://www.dnsstuff.com> for the current data). The reverse DNS entries are:
73.89.108.67.in-addr.arpa static-67-108-89-73.wig.tcwireless.us.
<http://www.DNSstuff.com/tools/ptr.ch?ip=67.108.89.73> [TTL=38400]
Mail
PASS
Connect to mail servers
OK: I was able to connect to all of your mailservers.
PASS
Mail server host name in greeting
OK: All of your mailservers have their host name in the greeting:
exchangesrvr.thompsonig.com:<br /> 220 exchangesrvr.thompsonig.com Microsoft
ESMTP MAIL Service, Version: 6.0.3790.3959 ready at Sat, 20 Oct 2007 08:53:17
-0400 <br />
PASS
Acceptance of NULL <> sender
OK: All of your mailservers accept mail from "<>". You are required (RFC1123
<http://www.DNSstuff.com/pages/rfc1123.htm> 5.2.9) to receive this type of
mail (which includes reject/bounce messages and return receipts).
PASS
Acceptance of postmaster address
OK: All of your mailservers accept mail to postmaster@xxxxxxxxxxxxxx (as
required by RFC822 <http://www.DNSstuff.com/pages/rfc822.htm> 6.3, RFC1123
<http://www.dnsstuff.com/tools/rfc.ch?detail=1123> 5.2.7, and RFC2821
<http://www.dnsstuff.com/tools/rfc.ch?detail=2821> 4.5.1).
PASS
Acceptance of abuse address
OK: All of your mailservers accept mail to abuse@xxxxxxxxxxxxxxx
INFO
Acceptance of domain literals
WARNING: One or more of your mailservers does not accept mail in the domain
literal format (user@[0.0.0.0]). Mailservers are technically required RFC1123
<http://www.DNSstuff.com/pages/rfc1123.htm> 5.2.17 to accept mail to domain
literals for any of its IP addresses. Not accepting domain literals can make it
more difficult to test your mailserver, and can prevent you from receiving
E-mail from people reporting problems with your mailserver. However, it is
unlikely that any problems will occur if the domain literals are not accepted
(mailservers at many common large domains have this problem).
exchangesrvr.thompsonig.com's postmaster@[67.108.89.73] response:<br /> >>>
RCPT TO:<postmaster@[67.108.89.73]><br /> <<< 550 5.7.1 Unable to relay for
postmaster@[67.108.89.73] <br />
PASS
Open relay test
OK: All of your mailservers appear to be closed to relaying. This is not a
thorough check, you can get a thorough one here
<http://www.abuse.net/relay.html> .
exchangesrvr.thompsonig.com OK: 550 5.7.1 Unable to relay for
Not.abuse.see.www.DNSreport.com.from.IP.206.192.63.161@xxxxxxxxxxxxx <br />
PASS
SPF record
You have an SPF record <http://www.openspf.org> . This is very good, as it will
help prevent spammers from abusing your domain. Your SPF record (I don't check
to see if it is well designed!) is:
"v=spf1 ip4:67.108.89.73 ~all" [TTL=86400]
WWW
INFO
WWW Record
Your www.thompsonig.com A record is:
www.thompsonig.com. A 69.25.72.149 [TTL=86400] [US]
PASS
All WWW IPs public
OK. All of your WWW IPs appear to be public IPs. If there were any private IPs,
they would not be reachable, causing problems reaching your web site.
PASS
CNAME Lookup
OK. Some domains have a CNAME record for their WWW server that requires an
extra DNS lookup, which slightly delays the initial access to the website and
use extra bandwidth. There are no CNAMEs for www.thompsonig.com, which is good.
INFO
Domain A Lookup
Your thompsonig.com A record is:
thompsonig.com. A 69.25.72.149 [TTL=86400]
Legend:
* Rows with a FAIL indicate a problem that in most cases really should be
fixed.
* Rows with a WARN indicate a possible minor problem, which often is not
worth pursuing.
* Note that all information is accessed in real-time (except where
noted), so this is the freshest information about your domain.
* Note that automated usage is not tolerated; please only view the DNS
report directly with your web browser.
From: exchangelist-bounce@xxxxxxxxxxxxx
[mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of Gabriel E. Rincon
Sent: Saturday, October 20, 2007 7:43 AM
To: exchangelist@xxxxxxxxxxxxx
Subject: [ExchangeList] Re: How to Clear Up Queues (and solve some of my
problems!)
John,
The likely problem with yahoo & hotmail& gmail Is that it will use reverse
lookup to ensure that the email is coming from a legit domain address.
For example, if you go to dnsstuff.com and put in your domain name to check
that all your dns records are correct, you will likely notice that the reverse
entry for the mail.mydomain.com is probably not there, or providing erroneous
info.
If you are authoiritative for your domain (you control all of your DNS
records), you need to make sure that the reverse zone (in my case
63.192.206-in-addr-arpa zone file) has an entry for the mx record.
It could also be that your ISP (if you are not your ISP) will have to enter a
record in their reverse zone file to recoird your MX record properly.
Hope this helps
Gabe Rincón
Computer Technologies
225-293-2844
From: exchangelist-bounce@xxxxxxxxxxxxx
[mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of John L. Gitzen II
Sent: Saturday, October 20, 2007 4:53 AM
To: exchangelist@xxxxxxxxxxxxx
Subject: [ExchangeList] Re: How to Clear Up Queues (and solve some of my
problems!)
Simon,
Thank you for the quick response. I started the process to set up SMTP
connectors, but my process kept failing because of authorization. As it turns
out I had two different problems with my DNS setup. Please note that DNS
primary runs on the DC which I did not set up. It was configured to not allow
Recursion, so my Exchange Server could never get external server address to
connect the SMTP connectors with. Once that was corrected my email started
flowing.
The problem I was having with setting up the SMTP connectors was also likely a
DNS issue. I had started to install DNS on my Exchange Server setting it up as
a Secondary zone with replication from the primary DNS, but once I got into the
wizard I got scared and cancelled the installation. This left DNS defined to
my server but not replicating. It had no entries, including pointers to my own
DC where my active directory also resides, so the wizard to define the SMTP
connector failed every time because the AD check failed to even find the AD
server.
Almost all of my email is now flowing in and out just great - except to my
yahoo.com email address. Since I use this address a lot to test and I initiate
a lot of email from it, I would like to get this corrected, so I am considering
the SMTP Connector route for this one domain. I posted an inquiry on
yahoo.com's Contact Us link but I don't expect any amazing solutions from them.
Has anyone ever had this problem and how did you approach the vendor? I think
my site or my personal email address may be on yahoo.com's grey list, but I
have no way to prove it. I know that the Troubleshooting Assistant shows the
email leaving my site and going to mta300.mail.mud.yahoo.com, but that is as
far as I can tell it gets. Also be advised that earlier yesterday I was able
send and receive from my yahoo.com email address
Thanks
John
Technology Applied
-----Original Message-----
From: exchangelist-bounce@xxxxxxxxxxxxx
[mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of Simon Butler
Sent: Wednesday, October 17, 2007 5:21 AM
To: 'exchangelist@xxxxxxxxxxxxx'
Subject: [ExchangeList] Re: How to Clear Up Queues (and solve some of my
problems!)
Quick way to deal with those messages while you wait for the DNS to clear is to
setup an SMTP connector to route email via your ISPs SMTP server.
http://www.amset.info/exchange/smtp-connector.asp
Also don't forget that the retry times for Exchange increase over time, so the
longer it goes the more time between retries. However setup an SMTP Connector
and the messages will be gone.
Finally - it isn't really the MX record that is causing the problem - but PTR
(aka reverse DNS) records. You need to speak to your ISP about those. Ideally
you should have the server announcing itself as the same name as on the reverse
DNS. Your current reverse DNS record looks like a dynamic allocation, so
messages will get rejected.
Simon.
--
Simon Butler
MVP: Exchange, MCSE
Amset IT Solutions Ltd.
e: simon@xxxxxxxxxxx
w: www.amset.co.uk
w: www.amset.info
Need cheap certificates for Exchange, compatible with Windows Mobile 5.0?
Go to http://www.certificatesforexchange.com/ for certificates for just $20 a
year.
________________________________
From: exchangelist-bounce@xxxxxxxxxxxxx
[mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of John L. Gitzen II
Sent: 17 October 2007 07:57
To: exchangelist@xxxxxxxxxxxxx
Subject: [ExchangeList] How to Clear Up Queues (and solve some of my problems!)
Hello Exchange Experts!
I have over 100 queues with SMTP Connector Entries for outgoing mail that is
not making it to their intended recipients. I have had some problems with my
DNS records and understanding how DNS works with my external webhosting company
and also my Internet Provider. I hope I have those correctly set now, but with
the lag in DNS records being refreshed and then Email servers recognizing the
changes I am frustrated to say the least waiting to see if my email problems
will clear up.
At this point I can not send out email from a user on my Exchange server to any
of the addresses I can query on - yahoo.com, gmail.com, Comcast.net or
charter.net. They all sit waiting on the remote server to respond.
So two questions -
1. How do I clear up these SMTP connector entries? Being an old school
mainframer, I am used to getting error messages, being able to look them up to
find the root cause and having tools I can run to tell what is going on. If
they are available for Exchange they are pretty well hidden. The closest I can
find is the Troubleshooting Assistant, but in my case it is not giving me back
anything I can use. On my last pass it told me that it had a fatal error
accessing active directory.
a. The two corrections listed were to try connecting to exchange server
analyzer without specifying a domain controller. I don't see where the tool
ever asks for a domain controller. Under advanced login options I could
specify a domain, but I don't use the advanced login, the id I am logged on
with is as high up in our Active Directory as you can get. I specify an
Exchange Server name and a Global Catalog Server Name. It won't run without
these.
b. The other possible solution says to specify a domain controller that is
running and is available to you. I only have 1 domain controller, it is
running, and it is available to me. I checked Active Directory on it and it is
working. I have accessed the Exchange portions of the Active Directory Users
on the same server, which is my exchange server that I am running my test on.
I have tried to reboot both servers - AAARGGH - Nothing changed, the same
results.
c. Regardless of this lame solution, I have reason to believe my outgoing
email is not making it to their intended SMTP connectors because the DNS MX
record at the site hosting my domain was pointing to mail.thompsonig.com
instead of exchangesrvr.thompsonig.com. The email going out was coming from
exchangesrvr.thompsonig.com, but when the servers to a DNS lookup on
thompsonig.com, it was finding mail.thompsonig.com.
exchangesrvr.thompsonig.com would match the *.thompsonig.com A record that
pointed to the web hosting IP address and not the ip address for my Exchange
Server. So now that this is fixed - how do I get my outgoing email moving
again and this stuff cleaned up
2. Second, is there a way I can test DNS and Email changes without having
to wait 24 to 48 hours? This is an eternity when you have the whole company
breathing down your back.
My domain is thompsonig.com. my ip address for my email server should be
67.108.89.73. my Exchange server FQDN is exchangesrvr.thompsonig.com.
Any and all advice is appreciated. Sorry for the long winded email, it is late.
John
Technology Applied
The more I learn the more I realize I don't know!
- References:
- [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- From: John L. Gitzen II
- [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- From: Gabriel E. Rincon
Other related posts:
- » [ExchangeList] How to Clear Up Queues (and solve some of my problems!)
- » [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- » [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- » [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- » [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- From: John L. Gitzen II
- [ExchangeList] Re: How to Clear Up Queues (and solve some of my problems!)
- From: Gabriel E. Rincon