gws226
asked on
Unable to telnet to destination
Experts this is actually a Exchange related question, but I suspect it will best be answered here.
I am attempting to telnet to a mail server located at 66.76.249.49 The connection is either accepted or not accepted. I have no affliation with the destination email server, all that I do know is that 2 of 3 unrelated sites I maintain cannot send email successfully to it.
So far I have not been able to precisely narrow down the root cause of why the connection is not accepted.
I have been able to eliminate an ISP/ route issue (I can connect from certain machines; the issue spans 3 different ISPs)
I think I have been able to eliminate telnet protocol issues (I can connect from one exchange 2007 SP2, but not another)
I have also tried different ISPs, and different networks with mixed results.
examples:(for testing purposes I have set my global outs the same for each test)
If it helps he 3 sites share a commonality in Firewall and antivirus products.
Site A/ ISP A
Server A: WinSBS2008- No success (exchange)
Server B Win2003 standard- Success
Server C: Win2003 standard- Success
Site B/ ISP A
ServerA: WinSBS2008- Success (exchange)
ServerB: Win2003 standard- Success
Site C/ ISP B
ServerA: Win2008/Exchange2007- No Success
WorkstationA: Windows 7- No Success
ServerB: Windows 2003 standard- Success
Any help appreciated
I am attempting to telnet to a mail server located at 66.76.249.49 The connection is either accepted or not accepted. I have no affliation with the destination email server, all that I do know is that 2 of 3 unrelated sites I maintain cannot send email successfully to it.
So far I have not been able to precisely narrow down the root cause of why the connection is not accepted.
I have been able to eliminate an ISP/ route issue (I can connect from certain machines; the issue spans 3 different ISPs)
I think I have been able to eliminate telnet protocol issues (I can connect from one exchange 2007 SP2, but not another)
I have also tried different ISPs, and different networks with mixed results.
examples:(for testing purposes I have set my global outs the same for each test)
If it helps he 3 sites share a commonality in Firewall and antivirus products.
Site A/ ISP A
Server A: WinSBS2008- No success (exchange)
Server B Win2003 standard- Success
Server C: Win2003 standard- Success
Site B/ ISP A
ServerA: WinSBS2008- Success (exchange)
ServerB: Win2003 standard- Success
Site C/ ISP B
ServerA: Win2008/Exchange2007- No Success
WorkstationA: Windows 7- No Success
ServerB: Windows 2003 standard- Success
Any help appreciated
You can use an online tool to verify your sites DNS and Blacklist status.
http://www.mxtoolbox.com/
That will give you an indication if you're being blocked and getting disconnected because of a blacklist / DNS issue.
http://www.mxtoolbox.com/
That will give you an indication if you're being blocked and getting disconnected because of a blacklist / DNS issue.
ASKER
1) I just get cannot connect on affected servers.
C:\>telnet 66.76.249.49 25
Connecting To 66.76.249.49...Could not open connection to the host, on port 25:
Connect failed
2) If the public IP at this sites were blacklisted then I would assume I would not be able telnet from any server at an affected site. (global out IPs are the same)
3) I will be happy to provide an SMTP conversation that will help. Thusfar I cannot establish the connection, so can't send any commands.
Here is a successful session from "ServerB @ Site C"
Welcome to Microsoft Telnet Client
Escape Character is 'CTRL+]'
Microsoft Telnet> o 66.76.249.49 25
220 garyreadnourcpa.com ESMTP Service ready
C:\>telnet 66.76.249.49 25
Connecting To 66.76.249.49...Could not open connection to the host, on port 25:
Connect failed
2) If the public IP at this sites were blacklisted then I would assume I would not be able telnet from any server at an affected site. (global out IPs are the same)
3) I will be happy to provide an SMTP conversation that will help. Thusfar I cannot establish the connection, so can't send any commands.
Here is a successful session from "ServerB @ Site C"
Welcome to Microsoft Telnet Client
Escape Character is 'CTRL+]'
Microsoft Telnet> o 66.76.249.49 25
220 garyreadnourcpa.com ESMTP Service ready
ASKER
@Gregory. This does not appear to be a blacklist issue.
Checking 68.143.140.98 against 104 known blacklists...
Listed 0 times with 4 timeouts.
Blacklist Status Reason TTL ResponseTime
AHBL OK 47
ANT OK 187
Backscatter.org OK 47
BURNT-TECH OK 16
CASA-CBL OK 62
CASA-CBL+ OK 62
CASA-CDL OK 62
CBL OK 62
CYBERLOGIC OK 62
CYMRU-BOGONS OK 78
DAN-TOR OK 140
DAN-TOREXIT OK 125
DEADBEEF OK 109
DNSBLINFO OK 125
DUINV OK 187
DULRU OK 187
EMAILBASURA OK 328
FABELSOURCES OK 187
FIVETEN OK 187
GIRL OK 187
GRIP OK 187
HIL OK 187
HIL OK 187
HILLI OK 203
ICMFORBIDDEN OK 218
IMP-SPAM OK 484
IMP-WORM OK 624
INTERSIL OK 218
ivmSIP OK 218
ivmSIP/24 OK 218
KEMPTBL OK 218
KUNDENSERVER OK 218
LASHBACK OK 218
LNSGBLOCK OK 218
LNSGBULK OK 218
LNSGDUL OK 218
LNSGMULTI OK 218
LNSGOR OK 218
LNSGSRC OK 203
MSRBL-Combined OK 203
MSRBL-Images OK 234
MSRBL-Phising OK 234
MSRBL-Spam OK 234
MSRBL-Viruses OK 234
NERD OK 234
NETHERRELAYS OK 234
NETHERUNSURE OK 234
NIXSPAM OK 234
NJABL OK 234
NJABLDUL OK 234
NJABLFORMMAIL OK 234
NJABLMULTI OK 234
NJABLPROXIES OK 234
NJABLSOURCES OK 234
NLKUNBLACKLIST OK 234
NLKUNWHITELIST OK 234
NOFALSEPOSITIVE OK 234
NOMOREFUNN OK 234
ORID OK 296
ORVEDB OK 296
OSPAM OK 296
PDL OK 296
PSBL OK 296
RANGERSBL OK 296
RATS-Dyna OK 296
RATS-NoPtr OK 296
RATS-Spam OK 296
RRBL OK 296
RSBL OK 296
SCHULTE OK 296
SDERB OK 296
SENDERBASE OK 296
SERVICESNET OK 296
SOLID OK 296
SORBS-BLOCK OK 296
SORBS-DUHL OK 296
SORBS-HTTP OK 296
SORBS-MISC OK 296
SORBS-SMTP OK 296
SORBS-SOCKS OK 296
SORBS-SPAM OK 296
SORBS-WEB OK 296
SORBS-ZOMBIE OK 296
SPAMCANNIBAL OK 296
SPAMCOP OK 312
Spamhaus-ZEN OK 312
SPAMSOURCES OK 312
SPEWS1 OK 312
SPEWS2 OK 312
SWINOG OK 312
TECHNOVISION OK 312
Tiopan OK 312
TRIUMF OK 312
UCEPROTECTL1 OK 312
UCEPROTECTL2 OK 312
UCEPROTECTL3 OK 312
VIRBL OK 312
WPBL OK 312
WSFF OK 312
ZONEEDIT OK 312
Checking 68.143.140.98 against 104 known blacklists...
Listed 0 times with 4 timeouts.
Blacklist Status Reason TTL ResponseTime
AHBL OK 47
ANT OK 187
Backscatter.org OK 47
BURNT-TECH OK 16
CASA-CBL OK 62
CASA-CBL+ OK 62
CASA-CDL OK 62
CBL OK 62
CYBERLOGIC OK 62
CYMRU-BOGONS OK 78
DAN-TOR OK 140
DAN-TOREXIT OK 125
DEADBEEF OK 109
DNSBLINFO OK 125
DUINV OK 187
DULRU OK 187
EMAILBASURA OK 328
FABELSOURCES OK 187
FIVETEN OK 187
GIRL OK 187
GRIP OK 187
HIL OK 187
HIL OK 187
HILLI OK 203
ICMFORBIDDEN OK 218
IMP-SPAM OK 484
IMP-WORM OK 624
INTERSIL OK 218
ivmSIP OK 218
ivmSIP/24 OK 218
KEMPTBL OK 218
KUNDENSERVER OK 218
LASHBACK OK 218
LNSGBLOCK OK 218
LNSGBULK OK 218
LNSGDUL OK 218
LNSGMULTI OK 218
LNSGOR OK 218
LNSGSRC OK 203
MSRBL-Combined OK 203
MSRBL-Images OK 234
MSRBL-Phising OK 234
MSRBL-Spam OK 234
MSRBL-Viruses OK 234
NERD OK 234
NETHERRELAYS OK 234
NETHERUNSURE OK 234
NIXSPAM OK 234
NJABL OK 234
NJABLDUL OK 234
NJABLFORMMAIL OK 234
NJABLMULTI OK 234
NJABLPROXIES OK 234
NJABLSOURCES OK 234
NLKUNBLACKLIST OK 234
NLKUNWHITELIST OK 234
NOFALSEPOSITIVE OK 234
NOMOREFUNN OK 234
ORID OK 296
ORVEDB OK 296
OSPAM OK 296
PDL OK 296
PSBL OK 296
RANGERSBL OK 296
RATS-Dyna OK 296
RATS-NoPtr OK 296
RATS-Spam OK 296
RRBL OK 296
RSBL OK 296
SCHULTE OK 296
SDERB OK 296
SENDERBASE OK 296
SERVICESNET OK 296
SOLID OK 296
SORBS-BLOCK OK 296
SORBS-DUHL OK 296
SORBS-HTTP OK 296
SORBS-MISC OK 296
SORBS-SMTP OK 296
SORBS-SOCKS OK 296
SORBS-SPAM OK 296
SORBS-WEB OK 296
SORBS-ZOMBIE OK 296
SPAMCANNIBAL OK 296
SPAMCOP OK 312
Spamhaus-ZEN OK 312
SPAMSOURCES OK 312
SPEWS1 OK 312
SPEWS2 OK 312
SWINOG OK 312
TECHNOVISION OK 312
Tiopan OK 312
TRIUMF OK 312
UCEPROTECTL1 OK 312
UCEPROTECTL2 OK 312
UCEPROTECTL3 OK 312
VIRBL OK 312
WPBL OK 312
WSFF OK 312
ZONEEDIT OK 312
Your first example shows that the server is not there or not responding to connections on port 25. Try first
ping -d 66.76.249.49 25
If you get a resonse then the server is there. If no reply try
tracert -d 66.76.249.49 25
How far does it get? It might be a routing problem
ping -d 66.76.249.49 25
If you get a resonse then the server is there. If no reply try
tracert -d 66.76.249.49 25
How far does it get? It might be a routing problem
ASKER
That was my first guess as well PeakPeak. But again, I can connect from SOME servers at each site, and not others. I would expect the routing issue (and blacklist for that matter to be universal)
First trace is from a station I cannot connect with.
C:\I>tracert 66.76.249.49
Tracing route to s66-76-249-49.pvymcmtc01.p
9.49]
over a maximum of 30 hops:
1 1 ms 1 ms 1 ms 68.143.140.97.nw.nuvox.net
2 3 ms 4 ms 4 ms se4-0-19c1.gnvlsc-vl-ca001
.57]
3 4 ms 3 ms 4 ms ge1-4.clmascsnea1.nw.nuvox
4 11 ms 11 ms 11 ms 64-128-71-1.static.twtelec
5 27 ms 26 ms 37 ms peer-01-ge-0-0-0-1.asbn.tw
9.10]
6 26 ms 26 ms 26 ms ashbosr01-10gex1-3.atw.sta
.219.33]
7 57 ms 58 ms 58 ms cdm-66-76-31-130.lfkn.sudd
30]
8 57 ms 58 ms 57 ms 66-76-232-25.tyrd.suddenli
9 58 ms 57 ms 57 ms 66-76-232-1.tyrd.suddenlin
10 85 ms 85 ms 85 ms 66-76-232-34.tyrd.suddenli
11 84 ms 85 ms 85 ms cdm-66-76-31-110.lfkn.sudd
10]
12 74 ms 75 ms 74 ms cdm-208-180-80-5.ukwn.sudd
.5]
13 76 ms 76 ms 75 ms cdm-208-180-80-162.ukwn.su
80.162]
14 76 ms 78 ms 77 ms cdm-208-180-81-134.ukwn.su
81.134]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24
This trace is from a working server
Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.
C:\>tracert 66.76.249.49
Tracing route to s66-76-249-49.pvymcmtc01.p
9.49]
over a maximum of 30 hops:
1 1 ms <1 ms <1 ms 68.143.140.97.nw.nuvox.net
2 3 ms 3 ms 3 ms se4-0-19c1.gnvlsc-vl-ca001
.57]
3 3 ms 3 ms 3 ms ge1-4.clmascsnea1.nw.nuvox
4 117 ms 65 ms 10 ms 64-128-71-1.static.twtelec
5 26 ms 26 ms 26 ms peer-01-ge-0-0-0-1.asbn.tw
9.10]
6 27 ms 26 ms 26 ms ashbosr01-10gex1-3.atw.sta
.219.33]
7 57 ms 62 ms 60 ms cdm-66-76-31-130.lfkn.sudd
30]
8 70 ms 57 ms 58 ms 66-76-232-25.tyrd.suddenli
9 59 ms 57 ms 56 ms 66-76-232-1.tyrd.suddenlin
10 101 ms 84 ms 84 ms 66-76-232-34.tyrd.suddenli
11 84 ms 84 ms 84 ms cdm-66-76-31-110.lfkn.sudd
10]
12 74 ms 74 ms 74 ms cdm-208-180-80-5.ukwn.sudd
.5]
13 75 ms 75 ms 75 ms cdm-208-180-80-162.ukwn.su
80.162]
14 88 ms 104 ms 95 ms cdm-208-180-81-134.ukwn.su
81.134]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 *
First trace is from a station I cannot connect with.
C:\I>tracert 66.76.249.49
Tracing route to s66-76-249-49.pvymcmtc01.p
9.49]
over a maximum of 30 hops:
1 1 ms 1 ms 1 ms 68.143.140.97.nw.nuvox.net
2 3 ms 4 ms 4 ms se4-0-19c1.gnvlsc-vl-ca001
.57]
3 4 ms 3 ms 4 ms ge1-4.clmascsnea1.nw.nuvox
4 11 ms 11 ms 11 ms 64-128-71-1.static.twtelec
5 27 ms 26 ms 37 ms peer-01-ge-0-0-0-1.asbn.tw
9.10]
6 26 ms 26 ms 26 ms ashbosr01-10gex1-3.atw.sta
.219.33]
7 57 ms 58 ms 58 ms cdm-66-76-31-130.lfkn.sudd
30]
8 57 ms 58 ms 57 ms 66-76-232-25.tyrd.suddenli
9 58 ms 57 ms 57 ms 66-76-232-1.tyrd.suddenlin
10 85 ms 85 ms 85 ms 66-76-232-34.tyrd.suddenli
11 84 ms 85 ms 85 ms cdm-66-76-31-110.lfkn.sudd
10]
12 74 ms 75 ms 74 ms cdm-208-180-80-5.ukwn.sudd
.5]
13 76 ms 76 ms 75 ms cdm-208-180-80-162.ukwn.su
80.162]
14 76 ms 78 ms 77 ms cdm-208-180-81-134.ukwn.su
81.134]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24
This trace is from a working server
Microsoft Windows [Version 5.2.3790]
(C) Copyright 1985-2003 Microsoft Corp.
C:\>tracert 66.76.249.49
Tracing route to s66-76-249-49.pvymcmtc01.p
9.49]
over a maximum of 30 hops:
1 1 ms <1 ms <1 ms 68.143.140.97.nw.nuvox.net
2 3 ms 3 ms 3 ms se4-0-19c1.gnvlsc-vl-ca001
.57]
3 3 ms 3 ms 3 ms ge1-4.clmascsnea1.nw.nuvox
4 117 ms 65 ms 10 ms 64-128-71-1.static.twtelec
5 26 ms 26 ms 26 ms peer-01-ge-0-0-0-1.asbn.tw
9.10]
6 27 ms 26 ms 26 ms ashbosr01-10gex1-3.atw.sta
.219.33]
7 57 ms 62 ms 60 ms cdm-66-76-31-130.lfkn.sudd
30]
8 70 ms 57 ms 58 ms 66-76-232-25.tyrd.suddenli
9 59 ms 57 ms 56 ms 66-76-232-1.tyrd.suddenlin
10 101 ms 84 ms 84 ms 66-76-232-34.tyrd.suddenli
11 84 ms 84 ms 84 ms cdm-66-76-31-110.lfkn.sudd
10]
12 74 ms 74 ms 74 ms cdm-208-180-80-5.ukwn.sudd
.5]
13 75 ms 75 ms 75 ms cdm-208-180-80-162.ukwn.su
80.162]
14 88 ms 104 ms 95 ms cdm-208-180-81-134.ukwn.su
81.134]
15 * * * Request timed out.
16 * * * Request timed out.
17 * * * Request timed out.
18 * * * Request timed out.
19 * * * Request timed out.
20 * * * Request timed out.
21 * * * Request timed out.
22 * * * Request timed out.
23 * * * Request timed out.
24 *
66.76.249.49 is dodgy... or on a dodgy network connection... I can't ping it from here in the UK and tracert hops all over the place and never completes...
are you sure mail.garyreadnourcpa.com isn't on a dial up connection or something. If you deal with people there then give them a call. They don't even have a working website so maybe the company has gone bust.
are you sure mail.garyreadnourcpa.com isn't on a dial up connection or something. If you deal with people there then give them a call. They don't even have a working website so maybe the company has gone bust.
Use this info to contact them (pulled from whois):
Related Domains For Sale or At Auction SeaCpa.com ($500) ShopCpa.com ($1,900) AlCpa.com ($488) ClickCpa.com ($795) CorpCpa.com ($1,999) NhCpa.com ($488) HiCpa.com ($500) CpaId.com ($490) ItCpa.com ($1,495) FullCpa.com ($1,795) CpaMaster.com ($1,700) OhCpa.com ($488)
PatCpa.com ($400) IlCpa.com ($488) CpaUk.com ($795)
1 2 3 More >
Registrant Search:"Cole Technology Group, Inc." owns about5 other domains Registrar History:1 registrar NS History:1 change on 2 unique name servers over 0 year. IP History:1 change on 2 unique name servers over 0 years. Whois History:1 record has been archived since 2010-01-07 . Reverse IP:11,995,251 other sites hosted on this server. DomainTools for Windows®
Now you can access domain ownership records anytime, anywhere... right from your own desktop! Find out more >
Registrant:
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
Domain Name: GARYREADNOURCPA.COM
Created on: 04-Jan-10
Expires on: 04-Jan-15
Last Updated on: 04-Jan-10
Administrative Contact:
Cole, Stu
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
(405) 360-2901 Fax --
Technical Contact:
Cole, Stu
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
(405) 360-2901 Fax --
Domain servers in listed order:
NS27.DOMAINCONTROL.COM
NS28.DOMAINCONTROL.COM
Related Domains For Sale or At Auction SeaCpa.com ($500) ShopCpa.com ($1,900) AlCpa.com ($488) ClickCpa.com ($795) CorpCpa.com ($1,999) NhCpa.com ($488) HiCpa.com ($500) CpaId.com ($490) ItCpa.com ($1,495) FullCpa.com ($1,795) CpaMaster.com ($1,700) OhCpa.com ($488)
PatCpa.com ($400) IlCpa.com ($488) CpaUk.com ($795)
1 2 3 More >
Registrant Search:"Cole Technology Group, Inc." owns about5 other domains Registrar History:1 registrar NS History:1 change on 2 unique name servers over 0 year. IP History:1 change on 2 unique name servers over 0 years. Whois History:1 record has been archived since 2010-01-07 . Reverse IP:11,995,251 other sites hosted on this server. DomainTools for Windows®
Now you can access domain ownership records anytime, anywhere... right from your own desktop! Find out more >
Registrant:
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
Domain Name: GARYREADNOURCPA.COM
Created on: 04-Jan-10
Expires on: 04-Jan-15
Last Updated on: 04-Jan-10
Administrative Contact:
Cole, Stu
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
(405) 360-2901 Fax --
Technical Contact:
Cole, Stu
Cole Technology Group, Inc.
PO Box 720696
Norman, Oklahoma 73070
United States
(405) 360-2901 Fax --
Domain servers in listed order:
NS27.DOMAINCONTROL.COM
NS28.DOMAINCONTROL.COM
ASKER
I spoke with the IT support firm for the site. Got the typical response... "everything is fine here, must be your problem"
Anyone have any additional suggestions?
Anyone have any additional suggestions?
well mxtoolbox.com says it can connect to it.
And I can telnet into port 25, but can't tracert it which is really weird
And I can telnet into port 25, but can't tracert it which is really weird
based on the traceroute, it appears that there is a loop in the router that leads into your final destination. This is not something you will be able to correct - it is strictly on their end.
Show them the traceroute to prove to them they are looping and never completing!
Good luck though - I had an issue with Cablevision and it took them 4 days to finally understand what I was saying and then a matter of minutes to fix it - - - go figure!
Show them the traceroute to prove to them they are looping and never completing!
Good luck though - I had an issue with Cablevision and it took them 4 days to finally understand what I was saying and then a matter of minutes to fix it - - - go figure!
ASKER
Thanks for the input JerryD.
Mind clarifiying for me a bit?
Where do you see the loop?
Why would it affect only a handful of servers trying to reach the destination and not others?
I would love to present "flakiness" as the reason, but if that were the case I would expect it to work sometimes but thusfar it either just works or takes a snooze.
Mind clarifiying for me a bit?
Where do you see the loop?
Why would it affect only a handful of servers trying to reach the destination and not others?
I would love to present "flakiness" as the reason, but if that were the case I would expect it to work sometimes but thusfar it either just works or takes a snooze.
ASKER CERTIFIED SOLUTION
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Nice done jerry. Suddenlink has probably routers with poorly programmed failovers, causing this erratic behavior
thank you - yup thats my thought on this as well...
Nope :)
ASKER
I appreciate both of your comments. I too felt like it was a router issue (as you peakpeak) but JerryD was best able to describe the most likely cause. Since it is an issue beyond our control we have gone ahead an informed the destination's IT provider. We have heard nothing back...
2) are each of your servers in the various sites static public IP addresses? If so, I would check to see if you are on any blacklists - that is *usually* the root cause of most of this kind of stuff.
3) if you telnet to the address from a command prompt, you can sometimes see what the reason is!
If you need more info on haveing an SMTP conversation via email, let me know and I cadig it up.