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19

Yes, it would be possible, but you will lose some important advantages if you choose to do so: If you point all services to the same DNS name, you can't put them onto separate servers any more without reconfiguring any client that refers to them. As an example: With different names, when the load on the server grows too much, you can simply offload the ...


15

A really tricky configuration error. By starting a line with neither a hostname, the zone name or the @ shorthand for the zone origin, becomes a continuation of the record above. ns2 IN A 2.2.2.2 ; Mail server IN MX 10 mail.example.com. is actually ns2 IN A 2.2.2.2 ; Mail server ns2 IN MX 10 mail.example.com. ...


12

If you don't know what you're doing, do Google Apps - 5 dollars per user per month.


8

RDNS is irrelevant - it only checks that the IP address maps back to the domain name use. So: x.x.x.x maps to smtp.hoster.domain then the MS must name smtp.hoster.domain. As an MX always contains the IN A record, no CNAME, that simply means you put in the hoster's / shared domain name there as FQDN that properly maps. Basically, I run a SMALL hosting ...


7

Can clarify what you mean by "handed" to an IMAP server? Are you trying to consolidate messages stored in several POP email accounts into one IMAP account? Is this a one time deal or ongoing? One-time deal: Use a desktop client like Thunderbird. Add each pop3 account in turn (you can give each one their own "inbox"), as well as the imap account. Download ...


5

Qmail keeps it's configurations files in /var/qmail/control: grep YOUR_DOMAIN /var/qmail/control/* Remove your domain from the following files: /var/qmail/control/rcpthosts /var/qmail/control/locals


5

it more depends on how many messages/sec will you have to handle rather than number of users. 8k users is not a lot and you can handle such load for typical home users without problems on any modern hardware. remember that postfix is MTA - will handle nicely mail routing / sending, but it does not provide access to the local mail store - you'll need ...


5

Two options: "NAT Reflection" is the term for getting your router to do the NAT for the outside address for traffic originating internally. How this is configured (or whether it can be) depends completely on your router. DNS view splitting. For this, you'd configure your DNS for internal systems to resolve the external name to the internal address, as ...


5

This is a complex theme, but do not forget one other element here - you also compare hardware of different generations. This is not ONLY a pure GHZ comparison, you may very well compare outdated opterons (8 cores only? - is that 2x4, that is a VERY slow core compare to todays) with a sandy bridge / Ivy bridge level Xeon. I would go with the Xeon, simply for ...


5

There is a lot more to your question than just cores and performance. How many concurrent users does your server need to support? Are you with one server and no redundancy? What is the acceptable downtime for your application? Have you done any benchmark of your development machine for this application to somewhat extrapolate performance? You may be ...


5

After the new mail server is ready to accept mail for your domain via smtp and serve mail via imap and or pop or the like, then you want to change the old server to forward mail to the new server. Get all this working BEFORE you change MX records. Then it doesn't matter if mail arrives at either the old or new server, since it all ends up at the new ...


4

"if a Gmail users sends a mail to my server which is then forwarded to Gmail again the mail never shows up in Gmail" This is probably not a spam situation, but it may be a situation of how "mail routing loops" are being detected based upon your description. Most email systems will have some form of "looping" detection in place, otherwise loops like this ...


4

The tutorial is from May 9th, 2010. v1.2.6 2009-10-05 The last dovecot version before that date v2.0.rc1 2010-07-02 The next dovecot version after that date So the tutorial probably will use a 1.x configuration, while nowadays we will use dovecot 2.x. Well and A LOT has changed in how the configuration is set since then. Now I found this ...


4

You can use whatever hostname that you like for your mailserver, but you do need should have an MX entry. With that said, I do like the idea of having a separate name for different roles. First, if/when it comes time to change hosts, you're in greater control of DNS and will suffer fewer problems due to external DNS caching.


4

Your mail server will need a PTR record pointing to it. This will allow reverse DNS to work. I don't trust mail servers which use a second level domain like example.com as too many spammers try to claim their name is one of the big name domains. You are better off using a name like mail.example.com. If you are using mail.example.com add an MX to your ...


4

"When this happened before, I saw what the IP address (outside our network) in the current sessions that looks like the culprit. So I added it in the blacklist using connection filter in exchange server." So what you are saying is anyone on the internet that can find your mail server will be allowed to send mail through it, except for this one ip address ...


4

Outgoing SMTP on port 25 is blocked by default for all Digital Ocean users. You'll need to contact them if you want it unblocked.


3

I prefer CentOS because I don't like how Debian/Ubuntu layout their apache/dns/dhcpd packages, but I have used Ubuntu Server LTS in a production server environment so I'll try to help. Ubuntu or Debian? Either/or seeing as Ubuntu is based on Debian. Both have lots of documentation and a large user base to get help from. If you choose Ubuntu, make sure to ...


3

Postfix is excellent. The documentation is very good, it's easy to configure and it has a very active community. In Postfix parlance, you want to use "virtual aliases" to handle your domains. I answered a question yesterday which describes how to do this. Sendmail can do all of these things and is installed by default (or was when I last used FreeBSD) but ...


3

What about PostFix? I'm currently working my way through a Linux [Ubuntu] based guide but there are a number of Step by Step guides for FreeBSD too Try Here or Here. Note that I know little about FreeBSD (or PostFix for that matter as I have not finished the installation yet!) or how well you know your way around it so I don't know how useful the second ...


3

Nothing really. They are both generally used as terms to describe a 'Mail Transfer Agent' or MTA. Now, in some implementations you'll see Mail Gateway used to describe a device that sits on the edge of your network, accepting mail, and running security scans against it. But really this is just another form of MTA running anti-virus and anti-spam software. ...


3

As per rfc5321 the mail delivery is done to the A address if MX is missing. So the following lines are not required for SMTP to work: mail.example.com. IN A 192.168.0.1 example.com. IN MX 10 mail.example.com. See also: http://en.wikipedia.org/wiki/MX_record#History_of_fallback_to_A


3

Switching the DNS record is by far the simplest and least invasive way of doing what you want to acheive, but be aware that it's not foolproof. Depending on how well behaved the clients DNS is, it may cache old records for an extended period of time. If a bit of downtime is acceptable, then set your TTL of your A record to a small value (say, 5-10 minutes). ...


3

The command is subject to the regular shell variable replacement rules, so just try replacing the single quotes with double quotes. | ${FORMAIL} -A "X-Subject-Is: $SUBJECT"


3

Remember that SMTP mail was designed to be pretty much like regular mail. You write a message, put it in an envelope, write the recipient address on the envelope), write the sender name on the envelope, hand it over to the postman and off it goes (sorry no stamp here). Even if you write the wrong sender (purposely or not) the message will reach its ...


3

This does not actually answers the question as you asked it, but anyway... I think the "right" thing to do is not to try to circumvent hotmail block, but to understand why your emails get blocked and proceed from there. I presume you are not the only service in the world who needs to send lots of emails to hotmail users, and I presume all these services ...


3

For setting up your email server and webmail, you need two things: an SMTP server, to send out messages, as you said, a way to read the received messages, that's the part you're actually asking for. The webmail will not actually be receiving the messages, it will only read or fetch them from somewhere. It is the smtp server (usually the same as the one ...


3

This seems to be a good case for Microsoft Exchange, with the assistance of someone well-versed in Exchange deployments. The main reasons I recommend that is that your users seem to be Outlook-based on the client side, you're seeing groupware functionality (calendar and contacts) and you have an Active Directory setup. Also, your document retention and ...


3

Your troubles at finding an answer are due to not looking at the right scope. The option as to which email to download is a feature of a POP client, not the POP server. A POP server is to simply provide all email for a given user; the client can then decide to download all messages or ones selectively. POP was developed when disk space and bandwidth were ...


3

A closer look at the basic access controls available should help you out; just specify the appropriate access map in smtpd_recipient_restrictions that denies access to those domains: smtpd_recipient_restrictions = check_recipient_access hash:/etc/postfix/blacklisted_domains, permit_mynetworks, reject_unauth_destination, permit and in ...



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