THE DEFINITIVE GUIDE TO SETTING UP A LINUX RELAY SERVER FOR MICROSOFT EXCHANGE SERVER

Transcription

1 THE DEFINITIVE GUIDE TO SETTING UP A LINUX RELAY SERVER FOR MICROSOFT EXCHANGE SERVER 2000/2003 With Mandriva Spring, Postfix, Spamassassin, Clamav... Index INTRODUCTION...2 What you will need: Mandriva Linux Spring A box with a DVD-ROM for the DVD version of Mandriva Spring A Ms Exchange 2000/2003 box that you want to protect A live working Internet connection (Preferrably broadband)....3 Install Mandriva Spring * Mail server (Postfix)... 3 * SSH server (Open ssh-server)... 3 * Line command tools...3 urpmi wget... 3 Remove Installation Media/Update Mandriva Sources:...3 a) Create a script file under /root called update sh...3 b) Goto and select your distro...4 c) Save your script and make it executable...4 d) Type the following in your putty window and watch it go...4 Install Spamassassin, Razor, Pyzor, DCC and Amavisd-new...5 urpmi spamassassin (Say yes to the dependencies prompt)...5 urpmi amavisd...5 urpmi razor...8 urpmi pyzor... 8 urpmi dcc...8 urpmi amavisd-new...8 Configure Postfix...10 Configure Relay Recipient Maps urpmi perl-ldap...12 Install and configure Clam-AV urpmi clamav...15 urpmi clamd Configure your Exchange Server Try to send an Written by Costamagna Gianfranco (costamagnagianfranco@yahoo.it) Pag 1

2 INTRODUCTION First a little explanation: this guide wants to be only a simple "how to" setting up a linux mail relay server for microsoft exchange This is very important because microsoft's system doesn't support any anti-virus, anti-spam programs (you can install some but it's very difficult to configure them ;-) If you use this guide, you acknowledge and agree that owner of this guide is not responsible for the availability of such external sites or resources, and do not endorse and is not responsible or liable for any content, advertising, products, or other materials on or available from such sites or resources. You further acknowledge and agree that owner of this guide shall not be responsible or liable, directly or indirectly, for any damage or loss caused or alleged to be caused by or in connection with use of or reliance on any such content, goods or this websites available on or through any such site or resource. This guide is made by lots of guides but you can see a similar here: and an "how to setting up a Microsoft Exchange Server" (Called "Down and Dirty Guide to setting up Exchange 2000/2003") here: There is a couple of linux how-to floating on the Internet that deal with this subject. As a matter of fact, those guides are what inspired to write this one. In the spirit of keeping it simple, let me recommend the Mandrake or as it's currently known Mandriva Linux distro. This guide has been written with this distro in mind. What you will need: 1. Mandriva Linux Spring (I'm sure this will work on Mandriva 2005 Limited edition, Mandrake 10.1 or even older versions. I just haven't tested it on anything earlier) 2. A box with a DVD-ROM for the DVD version of Mandriva Spring (The system specs do not have to be very high. It's basically going to be a mail server. Depending on the amount of mail you expect, size the machine accordingly. I installed it on an Intel Desktop with a single Pentium CPU (2.0 Ghz), Hdd 40Gb and 512MB of RAM. The computer wasn't my choice). Pag 2

3 3. A Ms Exchange 2000/2003 box that you want to protect. 4. A live working Internet connection (Preferrably broadband). STEP 1: Install Mandriva Spring with the following minimum packages and normal level security: * Mail server (Postfix) * SSH server (Open ssh-server) * Line command tools Ip Address Net Mask DNS Server Gateway Name Stealth.vallauri.net Domain Search vallauri.net you can install some tools like as traceroute, www-browser, links for resolving problem like route wrong, various problem... you must install wget because is used to download repository from bo.mirror.garr.it (I don't use curl because it can do some problem) urpmi wget STEP 2: Remove Installation Media/Update Mandriva Sources: It's important to remove the installation DVD or CD-ROM as the media of choice for your Linux installation and instead use on-line media anytime we want to install or update anything on this installation. The procedures below will help you accomplish this: a) Create a script file under /root called update sh or whatever you want. I usually name them by distro. For example, for Spring, I called it "update sh". Open up a ssh (putty) windows to your server. It's a lot easier doing it though putty than trying to type the sources in a console window manually. In a putty window it's just a matter of copy and paste. Be careful that the cut and paste must be done under Unix system because under Windows the enter key is stored by ASCII 10 and 13 (only one of them under Unix) In the putty windows type the following: Pag 3

4 vi update sh Enter the following lines: urpmi.removemedia -a urpmi --auto-select --auto --wget b) Goto and select your distro and then click on the "Proceed to STEP 2 button. Then, under "2) Select a mirror for each source" section under Core Distribution, check off the following: "Main", "Contrib", Main_Updates, "Contrib_Updates" as a bare minimum. Then click on the Proceed to STEP 3 button. This will generate a list of mirrors. Select them and copy the entire list. Go back to your putty window, click the "i" key to put the editor in insert mode and paste what you just copied from your browser in your putty window between the lines you type earlier. So, your screen should look similar to this: urpmi.removemedia -a urpmi --auto-select --auto --wget urpmi.addmedia --wget main ftp://bo.mirror.garr.it/mirrors/mandrake/official/2007.1/i586/media/main/release with media_info/hdlist.cz urpmi.addmedia --wget --update main_updates ftp://bo.mirror.garr.it/mirrors/mandrake/official/2007.1/i586/media/main/updates with media_info/hdlist.cz urpmi.addmedia --wget contrib ftp://bo.mirror.garr.it/mirrors/mandrake/official/2007.1/i586/media/contrib/release with media_info/hdlist.cz urpmi.addmedia --wget --update contrib_updates ftp://bo.mirror.garr.it/mirrors/mandrake/official/2007.1/i586/media/contrib/updates with media_info/hdlist.cz c) Save your script and make it executable. Type the following in your putty window: Presss the "ESC" key to take the editor out of insert mode. Then press "SHIFT ZZ" or "ESC, wq ENTER" to save your file and exit from vi. chmod 755 update sh You should use --wget parameter because curl can do problem to connect the mirror. Now you are ready to go. d) Type the following in your putty window and watch it go. Once completed, your sources are updated and your installation media has been removed../update sh you can also type: urpmi --auto-select --wget (or urpmi --auto-update --wget) to update packet in your distro. Pag 4

5 STEP 3: Install Spamassassin, Razor, Pyzor, DCC and Amavisd-new a) At the console prompt or a putty window type the following command: urpmi spamassassin (Say yes to the dependencies prompt) urpmi amavisd If urpmi command doesn't work you can add --wget after it. vi /etc/amavisd/amavisd.comf set $myhostname = 'Stealth.vallauri.net' (Remove sharp before $) Save the file: ESC Shift ZZ service amavisd start Say yes to the dependencies prompt. This will automatically install spamassassin and razor automatically. Configure spamassassin: If your mail server is behind a NAT firewall, you may consider setting up the trusted_networks and internal_networks in spamassassin's local.cf file. This is a well known problem with spamassassin on a private IP. Here's how to fix it. Edit the /etc/mail/spamassassin/local.cf file: vi /etc/mail/spamassassin/local.cf Add the trusted_networks and internal_networks line for every PUBLIC ip address your mail server is known for: trusted_networks trusted_networks internal_networks internal_networks (Obviously substitute your own public IP address(es)) Add the following lines still in the /etc/mail/spamassassin/local.cf file to configure spamassassin to use razor, pyzor and dcc: bayes_auto_learn 1 bayes_path /etc/mail/spamassassin/bayes bayes_file_mode 0666 use_razor2 1 razor_config /root/.razor/razor-agent.conf razor_timeout 10 use_pyzor 1 pyzor_timeout 10 pyzor_max 5 add_header all Pyzor _PYZOR_ use_dcc 1 dcc_timeout 10 dcc_home /var/lib/dcc dcc_path /usr/bin/dccproc Pag 5

6 Create a custom rule set for spamassassin by typing the following in the console: vi /etc/mail/spamassassin/sa_rules_update.sh Copy and paste the following into the file: #!/bin/sh PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin -O 71_sare_redirect_pre3.0.0.cf &> /dev/null -O 70_sare_bayes_poison_nxm.cf &> /dev/null -O 70_sare_html.cf &> /dev/null -O 70_sare_html4.cf &> /dev/null -O 70_sare_html_x30.cf &> /dev/null -O 70_sare_header0.cf &> /dev/null -O 70_sare_header3.cf &> /dev/null -O 70_sare_header_x30.cf &> /dev/null -O 70_sare_specific.cf &> /dev/null -O 70_sare_adult.cf &> /dev/null -O 72_sare_bml_post25x.cf &> /dev/null -O 99_sare_fraud_post25x.cf &> /dev/null -O 70_sare_spoof.cf &> /dev/null -O 70_sare_random.cf &> /dev/null -O 70_sare_oem.cf &> /dev/null -O 70_sare_genlsubj0.cf &> /dev/null -O 70_sare_genlsubj3.cf &> /dev/null -O 70_sare_genlsubj_x30.cf &> /dev/null Pag 6

7 -O 70_sare_unsub.cf &> /dev/null -O 70_sare_uri.cf &> /dev/null -O bogus-virus-warnings.cf &> /dev/null -O evilnumbers.cf &> /dev/null -O random.current.cf &> /dev/null -O 00_FVGT_File001.cf &> /dev/null -O 88_FVGT_uri.cf &> /dev/null -O 99_FVGT_DomainDigits.cf &> /dev/null -O 99_FVGT_Tripwire.cf &> /dev/null -O 99_FVGT_meta.cf &> /dev/null -O mime_validate.cf /etc/init.d/amavisd restart exit 0 (this script download some rules to update spamassassin) when you wouldn't see a command on bash you can put &> /dev/null after the command. Save the file and change the permissions to executable: Shift ZZ chmod 755 /etc/mail/spamassassin/sa_rules_update.sh Run the file and ensure there are no errors. On the console or putty window type: /etc/mail/spamassassin/sa_rules_update.sh Under the /etc/mail/spamassassin directory you should see a bunch of files ending in.cf. Examples are: bogus_virus_warnings.cf, etc. That means the rules have been updated for spamassassin. Now, you must schedule this script to run on a regular basis. On the console or putty window type the following to schedule a cron job: crontab -e Paste the following in your putty window: 30 3 */2 * * /etc/mail/spamassassin/sa_rules_update.sh &> /dev/null (This will schedule the script to run every two days on 3:30. Save the file: Shift ZZ b) At the console prompt or a putty window type the following command: Pag 7

8 urpmi razor (razor should be already installed...) (accept all dependencies) razor-admin -home=/etc/mail/spamassassin/.razor -register razor-admin -home=/etc/mail/spamassassin/.razor -create razor-admin -home=/etc/mail/spamassassin/.razor -discover urpmi pyzor (accept all dependencies) urpmi dcc (accept all dependencies) urpmi amavisd-new (amavis should be already installed...) Say yes to the dependencies prompt. This will automatically install amavisd-new. c) Configure amavisd by editing the /etc/amavisd/amavisd.conf: vi /etc/amavisd/amavisd.conf Hit "i" to start editing. Ensure the lines below are set as follows. Add them if they don't exist: This bypasses all virus checks. Not needed in this particular situation since we will be installing clamav further down. If you are having problems with clamav and cannot get it to work, it could potentially stop your mail server from operating. In that case, remove the # from in front of the line and it will bypass all virus checks. #@bypass_virus_checks_acl = qw(. ); Ensure you enter the domain your mailserver belongs to. This setting is VERY important and without this setting messages WILL NOT be tagged as spam in the subject line. $mydomain = 'vallauri.net'; This line ensures that ALL domains this server delivers mail for will be processed through the spam filter. Without this line, only the domain appearing in the $mydomain = line above will be processed through the spam = qw(. ); Ensure this line is commented out with the # symbol just like it looks here. #@local_domains_maps = ( [".$mydomain"] ); tagged as spam is passed but, subject is modified. $sa_spam_modifies_subj = 1; Add spam info headers. I suggest you set as high as possible. Setting to undef is highly recommended so that all mail headers are modified no matter what. $sa_tag_level_deflt = undef; Pag 8

9 Add 'spam detected' headers at that level. This is the minimum score the system will need to add spam headers to a message. It's pretty low. Start out low and increase the value as you see fit. If you start to get a lot of false positives, you should increase this value. $sa_tag2_level_deflt = 3; Triggers spam evasive actions $sa_kill_level_deflt = 15; Spam level beyond which a DSN is not sent $sa_dsn_cutoff_level = 9; The word appended to the subject line of spam s before passed to the end user $sa_spam_subject_tag = '***SPAM***'; Ensures spam is passed to the end user tagged as such. We never want the spam filter to kill messages. We want the end user to decide whether it's spam or not. $final_spam_destiny = D_PASS; # Or D_REJECT if you want to kill it Ensures s with bad headers is passed to the end user tagged as such. $final_bad_header_destiny = D_PASS; # Or D_REJECT if you want to block it $myhostname = 'Stealth.vallauri.net'; # must be a fully-qualified domain name! HIT "ESC" and then "SHIFT ZZ" to save your amavisd.conf file. Edit your /etc/postfix/master.cf file and add the following entry to it as follows or amavisd will simply not work: vi /etc/postfix/master.cf Add the following entry at the very bottom of your master.cf file right before the line ##### END OF CONTENT FILTER CUSTOMIZATIONS #####: smtp-amavis unix - - y - 2 smtp -o smtp_data_done_timeout=1200 -o disable_dns_lookups=yes Once done with the editing, hit SHIFT, ZZ to save the file. Now issue the following command for changes to take effect: service amavisd reload Pag 9

10 STEP 4: Configure Postfix The steps below outline how to configure postfix to receive for your Exchange box, forward it to amavisd-new which in turns processes it with spamassasin and razor and if passes all the checks it gets forwarded back to postfix which in turn delivers to your exchange box. a) Issue the following command at your putty prompt to edit your /etc/postfix/main.cf file: vi /etc/postfix/main.cf Hit "i" to edit the file, and make sure the settings below are set obviously substituting your info and/or adding lines as necessary: # User configurable parameters inet_interfaces = all #mynetworks_style = host local_recipient_maps = delay_warning_time = 4h Do not give out more info to potential hackers than necessary. A lot of people leave the server type and version number on this field. I say, just be as vague as possible. Your choice. smtpd_banner = vallauri.net ESMTP unknown_local_recipient_reject_code = 550 smtp-filter_destination_concurrency_limit = 2 lmtp-filter_destination_concurrency_limit = 2 smtpd_sasl_path = /etc/postfix/sasl:/usr/lib/sasl2 recipient_delimiter = + owner_request_special = no alias_maps = hash:/etc/postfix/aliases, hash:/var/lib/mailman/data/aliases content_filter = smtp-amavis:[ ]:10025 receive_override_options = no_address_mappings #empty_address_recipient = header_checks = regexp:/etc/postfix/header_checks #message_size_limit = remove this sharp if you don't want to block mail by message size In the following line you specify the domains that you will allow this server to relay mail for. Be careful here. Limit this to only your domains or you risk of becoming an open relay! relay_domains = vallauri.net Obviously your domain name goes here. Multiple domains can go there separated by commas mydomain = vallauri.edu #or vallauri.net Enter the FQDN for your box here myhostname = Stealth.vallauri.net Pag 10

11 In this field, ensure that you put the IP address of your network where you have your exchange server is and your domain name. mynetworks = /16, vallauri.edu This field actually makes the whole relay thing work. Make a note of the file and the path, we'll deal with it further down. transport_maps = hash:/etc/postfix/transport #myorigin = queue_minfree = 0 Enter RBL lists in the following field. Please be very careful which lists you pick. Some lists are ran by tyrrants and sometimes legitimate server go on there. Also, keep in mind, any matched to a list gets rejected at the door. Which means it doesn't even get to your server which means the user or you will NEVER see that . Be very wise about which lists you pick. maps_rbl_domains = sbl.spamhaus.org, relays.ordb.org, opm.blitzed.org, dun.dnsrbl.net smtpd_helo_restrictions = permit_mynetworks, warn_if_reject, reject_non_fqdn_hostname, reject_maps_rbl smtpd_recipient_restrictions = permit_mynetworks, reject_unauth_destination, reject_non_fqdn_recipient smtpd_sender_restrictions = reject_unauth_pipelining, reject_unknown_sender_domain, reject_non_fqdn_sender The field below is very very important. Make a note of it and we'll deal with it further down this guide. #relay_recipient_maps = hash:/etc/postfix/exchange_recipients Once done with the editing, hit SHIFT, ZZ to save the file. b) Next issue the following command at your putty prompt where vallauri.net is the name of the domain this server is going to be relaying for and is the actual IP address of your exchange server. You can add as many domains as you like. echo "vallauri.net smtp:[ ]" >> /etc/postfix/transport The following command will tell postfix to accept for ALL domains. I DO NOT recommend you process the following command unless you are 150% sure you know what you are doing. I merely put it there for reference. echo "* smtp:[ ]" >> /etc/postfix/transport After you add the previous line(s) in your transport file, issue the following commands. One command per line: Pag 11

12 postmap /etc/postfix/transport postfix reload service postfix restart You should first see the message postfix/postfix-script: refreshing the Postfix Mail system and then Shutting Down postfix and Starting Postfix. You should see no errors during this. If you do, go back and fix them. Then do the postfix reload and the service postfix restart commands again and look for error. If no error, life is good! Proceed to next step. This step is used if you want do download locally Active Directory from Exchange Server (if you want to block inexistent user from your relay server) STEP 5: Configure Relay Recipient Maps The steps below outline how to tell postfix who are valid recipients on your Exchange server so that the postfix server doesn't forward to invalid addresses on your domain and have your Exchange server logs fill up with undeliverable receipts. This step requires installing a few extra packages as well as running Chris Covington's getadsmtp.pl script to get all the recipients from your Exchange box. The recipients will be saved on the /etc/postfix/exchange_recipients file. Finally, when we verify that the script works, we will schedule to run at regular intervals with crond depending on how dynamic the accounts on our Exchange server are. 1. First, goto the following link: You will be presented with Christ Covington's getadsmtp.pl script. In your putty window, create the getadsmtp.pl under your /usr/bin directory as follows: vi /usr/bin/getadsmtp.pl Now, hit "i" to start editing the file, then select and copy everything from your browser which has the getadsmtp.pl script and paste it your putty window. Hit "ESC" to stop editing, and then "SHIFT ZZ" to save the file. (you can also download it typing /usr/bin/wget -O /usr/bin/getadsmtp.pl) 2. Next you must install Net::LDAP. In your console/putty window type: urpmi perl-ldap Accept the the dependencies and have it install automatically. 3. Most of the instructions below have been taken verbatim from I have copied and pasted them for convenience and redundancy. These instructions will guide you through configuring and running the getadsmtp.pl script against your exchange server to get a list of valid aliases. I have put some of my own comments where necessary: Important: your spamfilter box will require port 389 access to your Pag 12

13 Active Directory DC in order for this script to work, so adjust your firewalls accordingly! Open the getadsmtp.pl script in your editor: vi /usr/bin/getadsmtp.pl Enter the path to your recipient maps file by changing the line: $VALID = "/etc/postfix/example_recipients"; to: $VALID = "/etc/postfix/exchange_recipients"; Next you will need to enter either the Fully Qualified Domain Name (FQDN) of your Active Directory Domain Controller or you can enter the DC's local IP address. You may have to do the latter if your DC uses the "yourdomain.local" naming scheme since your spamfilter would not be able to resolve this address (unless you explicitly tell it). In any event, depending on your situation, this parameter may need some tweaking in order for the spamfilter to "talk" to the DC. If you only have one DC, make sure that both $dc1 and $dc2 lines are set with the same FQDN or IP address of your one and only DC. Change the lines that say: $dc1="domaincontroller1.example.com"; $dc2="domaincontroller1.example.com"; to: $dc1=" "; $dc2=" "; if you have a domain controller (and a LDAP controller) here... Where w.x.y.z is the local IP address of your DC, and Backup Domain Controller ($dc2), if you have one. Again, enter the same IP address on both fields if you only have one DC. Next, you will need to determine and enter the LDAP container of your user base. To do this you should download and install the Windows 2000/2003 Support Tools and install them on your AD DC. The tools are usually located under the /Support/Tools directory of your Windows 2000/2003 Server installation CD if you don't want to download them. Once you install the support tools, goto your Exchange server and click on Start/Run and then type in "mmc". You should be presented with the windows root console. Click on File and then "Add/Remove Snap-In". In the next window click on the "Add" button. In the following "Add Remove Standalone Snap-In" you should see a list of already installed snap-ins. If you installed the support tools correctly, you should see the "ADSI Edit" snap in. Click on it, and then click on "Add" and then click on "Close" and then "Ok". You should have the ADSI Edit snap-in under the Console Root window. Right-Click on ADSI Edit and then click on "Connect To". On the next window just click "OK". Now under the ADSI Edit in your Console Root you should see your domain. Expand the domain tree, then expand the "DC=" tree and then click on the "CN=" tree that contains your Exchange users. Unless you moved your users around different containers in your AD, this is most probably the "CN=Users" tree. Now on the label of your console root window. It should something similar to this: "Console Root\ADSI Edit\Domain [yourdc.yourdomain.tld]\dc=yourdomain,dc=tld\cn=users" where yourdc.yourdomain.tld is the FQDN of your DC. So, on the getadsmtp.pl line below, change Pag 13

14 the default values to the values of your domain using the settings you got from above: $hqbase="cn=accounts,dc=vallauri,dc=net"; Next, you will need to enter a username and password for a user in your Active Directory. This user does not need any special privileges but you should make sure that the user's password is set to not expire. The format of the user should be entered as "cn=username,cn=users,dc=example,dc=com". Again, I suggest you read the comments in the getadsmtp.pl script carefully. Note that because you are entering a password here in clear text, I would make sure that this script is only readable by root. Once you have the information you need, change the lines: $user="cn=infotest,cn=informatica,cn=studenti,cn=accounts,dc=vallauri,dc=net"; $passwd="infotest"; to the appropriate values. * Please note that if the password you use contains the $ sign (and perhaps others? I am not familiar with perl really, but some characters such as $ and probably also quotes have special meaning) you will have to escape them appropriatly with the backslash or perl will complain. For exaple, if your password is: pa$$word, you would have to enter: pa\$\$word here. Once you have made all the changes to the getadsmtp.pl script you should save it (hit Esc, and then :wq): save and exit vi. Now, make the script executable and test out the script and see if it works: chmod 755 /usr/bin/getadsmtp.pl /usr/bin/getadsmtp.pl If the script runs successfully, you should now have a file in /etc/postfix called exchange_recipients listing all your addresses. To verify this, issue the command: less /etc/postfix/exchange_recipients (of course, replace this with the file name you chose earlier, if needed). You should see a list scroll by with format similar to this: user1@domain.com OK user2@domain.com OK user2@domain2.com OK...etc. Some final comments: If you look at your main.cf file, you will see that the unknown_local_recipient_reject_code is set to 550. However, this directive does not control the rejection code for a recipient that is not listed in the relay_recipients_maps. The default rejection code for unknown users is 550, which is most likely what you want, but if you ever wanted to change it, the directive to change is unknown_relay_recipient_reject_code Pag 14

15 STEP 6: Install and configure Clam-AV At your putty window, type in the following to install Clam-AV: urpmi clamav urpmi clamd Configure clamd to run as the amavis user. Edit /etc/clamd.conf: vi /etc/clamd.conf Hit "i" to start editing, find the line that reads "User clamav" and change to user amavis like below: # Run as a selected user (clamd must be started by root). # Default: disabled User amavis Change the owner under /var/lib/clamav to amavis as follows: chown -R amavis:amavis /var/lib/clamav Start the clamd daemon: service clamd start STEP 7: Configure your Exchange Server First, a little explanation how this whole SPAM thing works with our current setup. Potential SPAM messages get received, they are processed, if found as spam, they are tagged as such in the headers and most notably for the user's sake, the subject of the gets appended with ***SPAM*** (If you followed this guide exactly) and it still gets delivered to the user. It's important to understand that potential spam does NOT get deleted but instead it's marked and passed to the user. Now, the user has two choices. If the really is spam the user can just delete it. If the spam filter screwed up and the did get tagged as spam even though it shouldn't have, the user has to have a way of telling you that the should not get tagged as spam anymore. Vice versa, if the spam filter missed an that should had been marked as spam but didn't, the user has to be able to tell you that this must be marked as spam next time. So we have to give the users a way of moving messages in two separate areas, one for SPAM and one for NON-SPAM or HAM if you will. Pag 15

16 STEP 8: Try to send an If you would try to send an to check if the server run correctly you can configure an account (under outlook express, windows mail or thunderbird) in your internal network and try so send a mail to yourself or at another account in your domain name (vallauri.edu) es: Name: Prova Costamagna Mail Address: infotest@vallauri.edu POP3: (posta.vallauri.edu or hostpost.vallauri.net) (your exchange server) SMTP: (Stealth.vallauri.net) (your relay server) Username: infotest Password: infotest Now you can send a mail with a virus or a spam to your account and, when you receive it, control property message to check if all is gone well). Be careful to send spam, because this server mark your mail address as spam for the future... Written by Gianfranco Costamagna costamagnagianfranco@yahoo.it THIS GUIDE IS RELEASED WITH ARTISTIC LICENCE. Pag 16