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Re: ISPmail Lenny tutorial ready

Michelle Konzack schrieb:
> Am 2009-07-19 04:14:33, schrieb Thomas Goirand:
>> Christoph Haas wrote:
>>> If the MySQL service becomes unavailable for Postfix then the sending
>>> server will get a 4xx temporary error. In a huge setup I'd probably set
>>> up monitoring to get noticed of such outages quickly. And I'd use a load
>>> balancer in front of two MySQL instances (master-slave replication).
>> MySQL replication only works with low loads. In fact, running MySQL over
>> the network has a HUGE performance penalty.
> This is, WHY I use PostgreSQL...  It performance miuch better.

That's a bold claim. Where is the benchmark report on that? I'm a big
friend of PostgreSQL, too, but replication has been a PITA so far.
PostgreSQL is nice for the SQL but not that superior to MySQL. Like
schema changes don't get replicated with Slony and the setup was nearly
a religious experience. MySQL replication is far from perfect and
requires third-party tools (maatkit, mylvmbackup) and a lot of luck (try
stopping a slave the wrong way and welcome data loss) but it performs well.

We are doing MySQL replication, too. The binlog stream takes up ~2 Mbps
and it takes rather fast servers to keep up with the disk IO load. So I
can hardly imagine what kind of hardware would be needed to replicate
100 Mbps of SQL stream as mentioned earlier. Besides how many changes
would you need to do per second to get SQL statements making up 10

> Spamfiltering MUST be individuual and if you give th user options,  like
> at <freenet.de>, the user can CHOOSE which he/she want. Global filtering
> is VERY dangerous.

I wonder how many users are smart enough to train a spam filter
correctly. The majority of mortals tells me they prefer a certain ISP
because the detect 99% spam without any ado. Global filtering is
dangerous but often the only choice.

> And of course, you can not use  /^dsl.*\..*/, /ppp.*\..*/  if  you  have
> hosted Domains from your customers, because most customers ARE  on  such
> lines.

Those users are supposed to use their ISPs mail relay. Blocking dynamic
IPs is done for a reason.

 (proudly not a consultant)

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