Sybase NNTP forums - End Of Life (EOL)

The NNTP forums from Sybase - forums.sybase.com - are now closed.

All new questions should be directed to the appropriate forum at the SAP Community Network (SCN).

Individual products have links to the respective forums on SCN, or you can go to SCN and search for your product in the search box (upper right corner) to find your specific developer center.

Replication across LAN

3 posts in General Discussion Last posting was on 2012-10-23 10:58:35.0Z
John Posted on 2012-10-23 01:40:24.0Z
Sender: 60ad.5085ec8e.1804289383@sybase.com
From: John
Newsgroups: sybase.public.rep-server
Subject: Replication across LAN
X-Mailer: WebNews to Mail Gateway v1.1t
Message-ID: <5085f588.6404.1681692777@sybase.com>
NNTP-Posting-Host: 172.20.134.41
X-Original-NNTP-Posting-Host: 172.20.134.41
Date: 22 Oct 2012 18:40:24 -0700
X-Trace: forums-1-dub 1350956424 172.20.134.41 (22 Oct 2012 18:40:24 -0700)
X-Original-Trace: 22 Oct 2012 18:40:24 -0700, 172.20.134.41
Lines: 12
Path: forums-1-dub!not-for-mail
Xref: forums-1-dub sybase.public.rep-server:9271
Article PK: 841889

Hi,

Config: ASE 15.x, RS 15.x

My interpretation of the Replication Design guide is to have
a Replcation Server at each site as the preferred approach.
I would like to understand if there is any reason why one
replication server canot be used to replicate with multiple
databases (<10 instances) dispersed across a LAN? Whereby a
LAN spans multiple physical sites.

Regards John


"Mark A. Parsons" <iron_horse Posted on 2012-10-23 02:30:23.0Z
From: "Mark A. Parsons" <iron_horse@no_spamola.compuserve.com>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.13) Gecko/20101207 Lightning/1.0b2 Thunderbird/3.1.7
MIME-Version: 1.0
Newsgroups: sybase.public.rep-server
Subject: Re: Replication across LAN
References: <5085f588.6404.1681692777@sybase.com>
In-Reply-To: <5085f588.6404.1681692777@sybase.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-Antivirus: avast! (VPS 120916-1, 09/16/2012), Outbound message
X-Antivirus-Status: Clean
NNTP-Posting-Host: vip152.sybase.com
X-Original-NNTP-Posting-Host: vip152.sybase.com
Message-ID: <5086013f$1@forums-1-dub>
Date: 22 Oct 2012 19:30:23 -0700
X-Trace: forums-1-dub 1350959423 172.20.134.152 (22 Oct 2012 19:30:23 -0700)
X-Original-Trace: 22 Oct 2012 19:30:23 -0700, vip152.sybase.com
Lines: 21
Path: forums-1-dub!not-for-mail
Xref: forums-1-dub sybase.public.rep-server:9272
Article PK: 870424

You can use a single repserver to take care of all your replication needs.

Now, whether or not a single repserver will provide the best performance is going to depend on your topology (see the
design guide for some examples), with 2 key factors being your network speed and the volume of data being processed by
the repserver.

Another consideration will be your latency requirements (ie, how much latency can your business users put up with?).

On 10/22/2012 19:40, John wrote:
> Hi,
>
> Config: ASE 15.x, RS 15.x
>
> My interpretation of the Replication Design guide is to have
> a Replcation Server at each site as the preferred approach.
> I would like to understand if there is any reason why one
> replication server canot be used to replicate with multiple
> databases (<10 instances) dispersed across a LAN? Whereby a
> LAN spans multiple physical sites.
>
> Regards John


Luc Van der Veurst Posted on 2012-10-23 10:58:35.0Z
From: "Luc Van der Veurst" <dba_azvub@hotmail.com>
Newsgroups: sybase.public.rep-server
References: <5085f588.6404.1681692777@sybase.com>
Subject: Re: Replication across LAN
Lines: 38
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 6.00.2900.5931
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157
X-RFC2646: Format=Flowed; Original
X-Forwarded: by - (DeleGate/5.8.7)
NNTP-Posting-Host: vip152.sybase.com
X-Original-NNTP-Posting-Host: vip152.sybase.com
Message-ID: <5086785b@forums-1-dub>
Date: 23 Oct 2012 03:58:35 -0700
X-Trace: forums-1-dub 1350989915 172.20.134.152 (23 Oct 2012 03:58:35 -0700)
X-Original-Trace: 23 Oct 2012 03:58:35 -0700, vip152.sybase.com
Path: forums-1-dub!not-for-mail
Xref: forums-1-dub sybase.public.rep-server:9273
Article PK: 870426


<John> wrote in message news:5085f588.6404.1681692777@sybase.com...
> Hi,
>
> Config: ASE 15.x, RS 15.x
>
> My interpretation of the Replication Design guide is to have
> a Replcation Server at each site as the preferred approach.
> I would like to understand if there is any reason why one
> replication server canot be used to replicate with multiple
> databases (<10 instances) dispersed across a LAN? Whereby a
> LAN spans multiple physical sites.

Say you have 2 physical locations, A and B, a dataserver at each
location, ASEServerA and ASEServerB.

If you have one replication server, it will run at one of the physical
locations, say A with repserver RepServerA.

Now, if ASEServerB goes down, or the network goes down,
RepServerA will keep the transactions in its stable queues until the
connection is reastablished. It's easy to increase the number of
stable queues to buffer the transactions and remove the queues
once the situtation returned to normal.

On the otherhand, if ASEServerA, RepserverA or the network goes down,
the transactions are kept in the transaction logs of the replicated
databases
and can fill them up. You'll have to alter the database size and give them
more transaction log space to leave all transactions in the log.

If you have a replication server at both locations, you don't have this
problem.

Luc.