SQL Anywhere database replication - Send frequency question

Author

Send frequency question

Edgard L. Riba

2005-12-31, 9:23 am

Hi,

I'm replicating between 3 ASA servers -one consolidated and two remotes -
(version 9.02.3124), with the possibility of adding another remote (for a
total of 4 servers) in early 2007.

The servers grow at a rate of about 200-250 MB per month, and I'm basically
replicating everything. The servers are connected via a TCP/IP network
with a bandwidth of about 256KB, and I'm using FILE based SQL Remote.

The idea behind this scenario is to have a "distributed" database, where
users at each of the 3 locations can work locally on their database.

Up to the minute replication of changes is not essential, although it is
desired by management that replication of changes occurs as often as
possible, and more importantly completely.

The question is how often can I set the "Send Frequency" parameter on the
consolidated and remote sites? Are there any rules of thumb.

I had it set up at 40 minutes at the consolidated, and every 15 minutes at
the remote sites, but I'm thinking that that was too often, and some of the
problems I'm having with replication (rows not replicating, even though
there are no referential intergrity violations)are caused by that. I have
set the up to 45 minutes at the remote sites, and 50 minutes at the
consolidated, but I've no idea whether these values are ok.

BTW, Merry Christmas and Happy New Year to all....

Thanks,
Edgard

Reg Domaratzki

2006-01-01, 11:23 am

> The question is how often can I set the "Send Frequency" parameter on the
> consolidated and remote sites? Are there any rules of thumb.

The volume of transactions being sent by dbremote is what I'd use to
determine how often to send. Given a log file growth of about 10MB per day,
that means that roughly every minute, the log file grows by 7kb. This sort
of volume can easily be handled by dbremote, even if you run dbremote every
minute on the consolidated.

> I had it set up at 40 minutes at the consolidated, and every 15 minutes at
> the remote sites, but I'm thinking that that was too often, and some of
the
> problems I'm having with replication (rows not replicating, even though
> there are no referential intergrity violations) are caused by that.

I don't believe that the send frequency you set could have any effect on
rows not replicating or RI violations. There is something else going on,
but I don't believe it's because of the send frequency. If you have
information that proves your point, I'd love to see it, although I'm going
away for a week, so you won't hear from me for a while.

--
Reg Domaratzki, Sybase iAnywhere Solutions
Certified SQL Anywhere Associate
Please reply only to the newsgroup

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"Edgard L. Riba" <elriba at rimith dot com> wrote in message
news:43b69e6e$1@foru
ms-1-dub...
> Hi,
>
> I'm replicating between 3 ASA servers -one consolidated and two remotes -
> (version 9.02.3124), with the possibility of adding another remote (for a
> total of 4 servers) in early 2007.
>
> The servers grow at a rate of about 200-250 MB per month, and I'm
basically
> replicating everything. The servers are connected via a TCP/IP network
> with a bandwidth of about 256KB, and I'm using FILE based SQL Remote.
>
> The idea behind this scenario is to have a "distributed" database, where
> users at each of the 3 locations can work locally on their database.
>
> Up to the minute replication of changes is not essential, although it is
> desired by management that replication of changes occurs as often as
> possible, and more importantly completely.
>
> The question is how often can I set the "Send Frequency" parameter on the
> consolidated and remote sites? Are there any rules of thumb.
>
> I had it set up at 40 minutes at the consolidated, and every 15 minutes at
> the remote sites, but I'm thinking that that was too often, and some of
the
> problems I'm having with replication (rows not replicating, even though
> there are no referential intergrity violations)are caused by that. I
have
> set the up to 45 minutes at the remote sites, and 50 minutes at the
> consolidated, but I've no idea whether these values are ok.
>
> BTW, Merry Christmas and Happy New Year to all....
>
> Thanks,
> Edgard
>
>

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