Category Archives: MS Exchange server

Homework for attendees of my session at NT Konferenca 2007 / Domača naloga za udeležence mojega predavanja na NT Konferenci 2007

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1.) Preglejte stanje svojih domenskih zapisov: http://www.dnsreport.com
2.) Preglejte, ali so vaši poštni strežniki že na kakšni od obstoječih črnih list: http://www.dnsstuff.com
3.) Preverite, da imate pravilne MX zapise ter A zapise. Preverite, da se ujema A zapis z PTR (reverse) zapisom (npr. posta.podjetje.si se razreši v 123.123.123.123 in nazaj iz 123.123.123.123 naj se razresi v posta.podjetje.si)
4.) Preverite server greeting z ukazom telnet posta.podjetje.si 25 odgovoriti vam mora z tromestno številko + A zapisom
5.) Veliko vprašanj se je nanašalo na scenarij:
Imam domeno podjetje.si ter domeno podjetje.eu. Kako nastavim poštni strežnik za obe domeni.
Poleg standardnih nastavitev Recipient policy na strežniku Exchange na DNS nivoju stvar uredimo takole:
Za podjetje.si naredimo A zapis posta.podjetje.si ter PTR posta.podjetje.si ter nastavimo MX zapis z utežjo 10 na posta.podjetje.si
Za podjejt.eu dodamo MX zapis, ki kaže na posta.podjetje.si – s tem načinom pravilno in po RFCju skonfiguriramo poštni strežnik tako, da bo sprejemal pošto za obe domeni.

Exchange 2007 – Tips and tricks II / Exchange 2007 – Triki in nasveti II

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Here we are with first document about some basic things that you need to know and need to configure for your Exchange 2007 to work properly… Check the Links section! 🙂 / Tukaj je moj prvi dokument z informacijami, ki jih potrebujete za pravilno delovanje vašega Exchange 2007 sistema… Preglejte sekcijo s povezavami! 🙂

Exchange 2007 h4rdc0re.pdf

First Slovenian “white list” of safe mail servers / Prva slovenska “bela lista” varnih poštnih strežnikov

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In MMC Mostovna we have started a new technological project. This is first Slovenian white list of (slovenian) safe/trusted mail servers. The white-list is freely available but in BETA phase for now. I hope it will be ready soon. For testing just enter the name: si-whitelist.mostovna.com in your mail server and allow records that get code 127.0.0.1. You can get more info by sending e-mail to info(AT)si-whitelist.mostovna.com / V MMC Mostovna smo začeli z novim tehnološkim projektom, prvo slovensko “belo listo” varnih (slovenskih) poštnih strežnikov. Lista je prosto dostopna vendar za enkrat v BETA fazi. Upamo, da bo kmalu opravljena faza testiranj. Za testiranje liste lahko v nastavitve vaših poštnih strežnikov vpišete naslov: si-whitelist.mostovna.com in eksplicitno dovoljujete vse zapise, za katere dobite odgovor 127.0.0.1. Za več informacij smo vam na voljo na info(AT)si-whitelist.mostovna.com.

Exchange 2007 – Tips and tricks… / Exchange 2007 – Triki in nasveti…

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I will explain just in few words the major differences / changes that I encountered after a deployment of Microsoft Exchange 2007. / Z nekaj besedami vam bom opisal spremembe, ki sem jih srečal ob namestitvi Microsoft Exchange 2007 – sporočilnega sistema.

1. GUI and Powershell / Grafični vmesnik in “Močnostni ukazni poziv 🙂 (Powershell)”
Ok… You can do some basic stuff using GUI interface called Exchange Management Console.
In my configuration Exchange 2007 was installed on a single server so it is running:
– Mailbox role
– Hub transport role
– Client access role
MSExchange.org article about Exchange 2007 roles

Konfiguracija Exchange 2003 SP2 strežnika za filtriranje proti črnim listam, uporaba Intelligent message filter-ja ter Sender ID procesiranje / Configuration of Exchange 2003 SP2 to filter mail using black lists, usage of Intelligent message filter and Sender ID processing

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Konfiguracija Exchange 2003 SP2 strežnika za filtriranje proti črnim listam, uporaba Intelligent message filter-ja ter Sender ID procesiranje / Configuration of Exchange 2003 SP2 to filter mail using black lists, usage of Intelligent message filter and Sender ID processing

Nekaj zlatih pravil na katere moramo biti pozorni pri konfiguraciji poštnih strežnikov. / Some rules to be aware of when configuring mail servers.
DNS nivo / DNS layer

1. MX zapis mora obstajati / MX record must exist
Za test lahko v ukazni vrstici vpišete ukaz / For testing you can try to get the MX record using nslookup command:
nslookup
set type=MX
company.com
Kot rezultat bi morali dobiti / As result you should get:
company.com MX preference = 10, mail exchanger = mail.company.com

2. Forward in reverse DNS zapis se morata ujemati / Forward and reverse DNS record must be the same
Primer / Example:
Recimo, da MX zapis za domeno company.com kaže na poddomeno domene company.com in sicer na mail.company.com. V primeru, da izvršimo ukaz ping v ukazni vrstici dobimo rezultat: / Let say, that MX record for domain name company.com points to subdomain of company.com – mail.company.com. In this case you can check by pinging hostname and get the result:

C:>ping mail.company.com
Pinging mail.company.com [123.123.123.123] with 32 bytes of data:
Reply from 123.123.123.123: bytes=32 time=119ms TTL=238 …

Ce pa izvršimo ukaz, ki nam iz IP naslova razreši DNS zapis moramo dobiti rezultat: / If we try to make a reverse lookup we should get the same result:

C:>ping -a 123.123.123.123
Pinging mail.company.com [123.123.123.123] with 32 bytes of data:
Reply from 123.123.123.123: bytes=32 time=111ms TTL=238
…

Nivo poštnega strežnika (SMTP strežnika) / Mail server layer (SMTP server)

SMTP strežnik se mora oglasiti z istim imenom, kot je vpisan v MX zapisu – v našem primeru: mail.company.com. To pa lahko preizkušamo tako, da se z uporabo programa telnet povezemo na poštni strežnik na portu 25. / SMTP server should present with the same name as a name in MX record. In our case this is mail.company.com. This can be tested using telnet program connecting to port 25 of our mail server.
Kot rezultat bi morali dobiti: / As a result you should get:

220 mail.company.com Microsoft ESMTP MAIL Service, Version: 6.0.3790.1830 ready at Mon, 5 Feb 2007 23:07:34 +0100

http://www.dnsreport.com – preverite nastavitve svoje domen / check your domain name configuration
http://www.dnsstuff.com – dodatna orodja za pregled DNS zapisov / additional tools for checking DNS records
http://www.microsoft.com/mscorp/safety/content/technologies/senderid/wizard/ – Sender policy framework – generator TXT zapisa / Sender policy framework TXT record generator

  I. del / Part I. – Message delivery properties – general
(wink source) 

 II. del / Part II. – Message delivery properties – Connection filtering
(wink source) 

 III. del / Part III. – Message delivery properties – IMFv2 / Sender ID filtering
(wink source) 

 IV. del / Part IV. – Activate filters on SMTP server
(wink source) 

 V. del / Part V. – SMTP server name

Microsoft SMTP limanica / Microsoft SMTP Tarpit

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Z orodjem, ki ga lahko poberete na spodnji povezavi (.reg in .bat datoteki) lahko enostavno aktivirate 10 sekundno limanico na vašem SMTP servisu (deluje tudi z Exchange 2003). Z upočasnitvijo SMTP komunikacije pripomorete k zmanjšanju SPAM-a v vaših e-poštnih nabiralnikih. / With the tool that you can download (.reg and .bat files) you can very quickly enable 10 seconds tarpit of your SMTP servis (it works also on Exchange 2003). With reduction of SMTP coversation speed you get less SPAM in your mailboxes.

Microsoft SMTP tarpit.zip
Microsoft SMTP tarpit-5.zip – v primeru, da ste imeli kakšno težavo s 10 sekundnim zamikom je tu na voljo še reg datoteka s 5 sekundnim zamikom. / if you encountered any problems with 10 sec. tarpit you can try with this registry file with 5 sec. delay.

Keywords:
SMTP tarpit, SMTP tarpitting, Exchange 2003 tarpitting, Exchange 2003 tarpit, SMTP delay

Sources:
http://support.microsoft.com/kb/842851
http://www.petri.co.il/tar_pitting_exchange_2003.htm
http://msexchangeteam.com/archive/2004/12/06/275851.aspx