Hi,
On 18 May 2005, at 20:57, Kevin Baker wrote:
So David,
Do you have any kind of howto on the DRBD?
This is probably useful: ftp://ftp.software.ibm.com/software/data/
pubs/papers/db2halinux.pdf
It describes (among other things) setting up drbd for db2...(which is
no different from setting up drbd for pgsql...)
We've done some tests with postgresql and drbd recently and it seems
to work quite well.
How is the latency?
The latency depends on which protocol (of three) is used:
A: A write operation is complete as soon as the data is written
to disk and sent to the network
B: A write operation is complete as soon as a reception
acknowledgement arrives
C: A write operation is complete as soon as a write
acknowledgement arrives.
So it is a trade-off between safety and speed (isn't it always...)
regards,
Leander
How do you have the machines connected?
- dedicated (crossover) or normal ethernet
I considered this before as a way to replicate Cyrus for a
standby failover solution... but it look kind of complex,
which is why I started looking into DBMail.
Thanks,
Kevin
Well I need psql because I have a large need of triggers,
stored
proceedures and views. At the time I implemented most all
of that
stuff was "coming soon" in mysql.
I can work around replication with other devices, but I
can't
work around triggers.
Thanks for the help, I'll stick with DRBD replicating
psql.
--
David A. Niblett | email: [EMAIL PROTECTED]
Network Administrator | Phone: (352) 334-3400
Gainesville Regional Utilities | Web: http://www.gru.net/
-----Original Message-----
From: Simon Lange [mailto:[EMAIL PROTECTED]
Sent: Wednesday, May 18, 2005 1:02 PM
To: 'DBMail mailinglist'
Subject: RE: [Dbmail] DbMail in a ISP Cluster
Well when we did evaluate pgsql it didnt cover
replication. maybe u are
right that they dont implement replication because there
are thridparty
solutions available. but ur reffered solution is still
unstable (just read
their mailinglists and checked up their versions) and if
ppl use it for
productive purposes... -- well their business ;) however,
i could not find
any stable solution for circle replication for pgsql so
far. maybe there are
sum available but why searching if there is a
databaseserver which is fast
efficient and has replication built in (and in the next
major update also
native clustering)? it was no meant as an offense but its
a good question:
why usin pgsql-without-replication + thirdparty
replication and not using
mysql-WITH-replication?!
be sure i DO understand pgsql and i know why im not using
it. :) i never
meant to piss on pgsql. ok i would never use it for our
servers but thats my
opinion. ;) so u dont piss on me just because mysql has
the better
replication system built-in! ;) and as far as i can
remember the inital
question to this thread was if there are ppl out with
dbmail/clustering
experience... yes there are...
regards
Simon
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf
Of Matthew T. O'Connor
Sent: Wednesday, May 18, 2005 6:42 PM
To: DBMail mailinglist
Subject: Re: [Dbmail] DbMail in a ISP Cluster
The Postgresql development team made an intentional design
decided not to
include any one replication system into the main CVS tree
simply because
there are many types of fundamentally different
replication that serve
different purposes.
Slony is well tested, and is used in many production
environments. It is a
master-slave replication system, it works quite well and
is supported by the
slony team. I would not call it non-native. In addition
there are several
other replication implementation that serve different
purposes, some are
commercially supported by a vendor.
Please don't spread FUD about a system you don't
understand. I have not and
would not say a single negative thing about mysql or its
replication because
I don't have experience with it.
Matt
Simon Lange wrote:
varieties means ports?! branches of the original pgsql
source?! or are
these thridparty solutions which add external
functionalities which
pgsql does not provide? however, i would prefer a native
replication
instead a workaround.
;) especially on productive environments. ;)
however dbmail/mysql provides a tested and working
clustering (circle
replication) with on fail solution for all those who may
need it. so
why using a pgsql with non-native replication if there is
a stable
native mysql replication solution available?
regards
Simon
Simon Lange //Director
========================
www.polynaturedesign.com
+49[0]4131 220121 PHONE
+49[0]4131 224730 FAX
+49[0]16090300077 CELL
========================
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
Behalf Of Matthew T. O'Connor
Sent: Wednesday, May 18, 2005 5:58 PM
To: DBMail mailinglist
Subject: Re: [Dbmail] DbMail in a ISP Cluster
Postgresql does support replication, in fact there are
several
different varieties of it available, check out slony1
among others.
What it doesn't support is automatic failover.
Simon Lange wrote:
pgsql does not support replication. thats why we do use
mysql -
clustering is announced for mysql5 :D
if a database goes down, exim recognizes this and
temporaly refuses
any mails which causing foreign mta to address the other
mta...
regards
Simon
Simon Lange //Director
========================
www.polynaturedesign.com
+49[0]4131 220121 PHONE
+49[0]4131 224730 FAX
+49[0]16090300077 CELL
========================
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
Behalf Of Niblett, David A
Sent: Wednesday, May 18, 2005 5:04 PM
To: '[email protected]'
Subject: [Dbmail] DbMail in a ISP Cluster
What are you all using to cluster PostgreSQL? I looked
at the
master/slave replication that comes with Postgres. It
seems fine if
you want to replicate the data, but how do you get
dbmail to switch
databases when there is a failure?
I'm currently using drbd to replicate the disk block
device that my
postgres database is stored on, then only run postgres
on the "primary"
machine.
Linux heartbeat fails and starts the services on the
"secondary"
machine shold the first one croak.
--
David A. Niblett | email:
[EMAIL PROTECTED]
Network Administrator | Phone: (352) 334-3400
Gainesville Regional Utilities | Web:
http://www.gru.net/
______________________________________________
