Shared Disk Secondary
Reinhard (IDS 12.10 on Solaris 10) restarts his primary during maintenance to clear all user sessions, but the SDS secondary then shuts down when the primary comes back, breaking a read-availability SLA. Madison Pruet confirmed bluntly that this SDS behaviour cannot be avoided. The suggested workaround instead of a restart was to use administration/single-user mode (onmode -j, plus a checkpoint, e.g. onmode -cjy) to drop sessions and then onmode -m back, which should leave the SDS running; alternatives floated were failover via Connection Manager or using HDR/RSS as the read-only node. Reinhard said he would try the onmode -j approach, but no test result is recorded.
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Hi, my environment. Informix Server 12.10, Solaris 10 Is it possible not to shut down and restart a SDS-Server automatically, triggered by the shutdown and restart of a primary? Background: We have to restart the primary to stop all sessions during maintenance periods but we do not want the SDS-Server to be restarted. The reading access to the databases on the SDS-Server should not be interrupted because of a SLA with a customer. TIA Reinhard.
Hi, Reinhard. Your SDS secondary will not shutdown automatically. Secondary nodes in Informix are not automatically shutdown, in case of primary failure/shutdown. Informix failover to an SDS secondary is not also automatically done. So, if you want it to become the new primary node of cluster, during your maintenance period, you should use CM. Check this link for some examples of failover configurations in clusters: http://www.ibm.com/support/knowledgecenter/en/SSGU8G_11.50.0/com.ibm.adref.doc/i ds_adr_1111.htm?sc=_latest Hope it helps. Best regards Atenciosamente, Alexandre Marini [http://mcsoftware.com.br/mc_conteudo/assinaturas/logoassinatura.png] alexandre@mcsoftware.com.br<mailto:alexandre@mcsoftware.com.br><tel:+55%2011%209 76-030-358><tel:+55%2011%202594-0048> www.mcsoftware.com.br<http://www.mcsoftware.com.br>; [http://mcsoftware.com.br/mc_conteudo/assinaturas/arquiteturalogo.png] ________________________________ De: ids-bounces@iiug.org <ids-bounces@iiug.org> em nome de Habichtsberg, Reinhard <RHabichtsberg@arz-emmendingen.de> Enviado: segunda-feira, 21 de novembro de 2016 09:04:05 Para: ids@iiug.org Assunto: Shared Disk Secondary [38175] Hi, my environment. Informix Server 12.10, Solaris 10 Is it possible not to shut down and restart a SDS-Server automatically, triggered by the shutdown and restart of a primary? Background: We have to restart the primary to stop all sessions during maintenance periods but we do not want the SDS-Server to be restarted. The reading access to the databases on the SDS-Server should not be interrupted because of a SLA with a customer. TIA Reinhard. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.
Thanx, Alexandre, sure I didn't point it out properly. There is no need to make the SDS the new primary node. You are right, the SDS doesn't shut down with the primary. It shuts down when the primary is back again. I want to avoid exactly that behavior if possible. Best regards Reinhard. -----Ursprüngliche Nachricht----- Von: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] Im Auftrag von Alexandre Marini Gesendet: Montag, 21. November 2016 12:22 An: ids@iiug.org Betreff: Re: Shared Disk Secondary [38176] Hi, Reinhard. Your SDS secondary will not shutdown automatically. Secondary nodes in Informix are not automatically shutdown, in case of primary failure/shutdown. Informix failover to an SDS secondary is not also automatically done. So, if you want it to become the new primary node of cluster, during your maintenance period, you should use CM. Check this link for some examples of failover configurations in clusters: http://www.ibm.com/support/knowledgecenter/en/SSGU8G_11.50.0/com.ibm.adref.doc/i ds_adr_1111.htm?sc=_latest Hope it helps. Best regards Atenciosamente, Alexandre Marini [http://mcsoftware.com.br/mc_conteudo/assinaturas/logoassinatura.png] alexandre@mcsoftware.com.br<mailto:alexandre@mcsoftware.com.br><tel:+55%2011%209 76-030-358><tel:+55%2011%202594-0048> www.mcsoftware.com.br<http://www.mcsoftware.com.br>; [http://mcsoftware.com.br/mc_conteudo/assinaturas/arquiteturalogo.png] ________________________________ De: ids-bounces@iiug.org <ids-bounces@iiug.org> em nome de Habichtsberg, Reinhard <RHabichtsberg@arz-emmendingen.de> Enviado: segunda-feira, 21 de novembro de 2016 09:04:05 Para: ids@iiug.org Assunto: Shared Disk Secondary [38175] Hi, my environment. Informix Server 12.10, Solaris 10 Is it possible not to shut down and restart a SDS-Server automatically, triggered by the shutdown and restart of a primary? Background: We have to restart the primary to stop all sessions during maintenance periods but we do not want the SDS-Server to be restarted. The reading access to the databases on the SDS-Server should not be interrupted because of a SLA with a customer. TIA Reinhard. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.
Is it possible to avoid a SDS-Server shuts down when the Primary is stopped and restarted? TIA Reinhard.
blockquote, div.yahoo_quoted { margin-left: 0 !important; border-left:1px #715FFA solid !important; padding-left:1ex !important; background-color:white !important; } No. Sent from Yahoo Mail for iPad On Tuesday, November 22, 2016, 4:42 AM, REINHARD HABICHTSBERG <rhabichtsberg@arz-emmendingen.de> wrote: Is it possible to avoid a SDS-Server shuts down when the Primary is stopped and restarted? TIA Reinhard. ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.
Thank you, Madison. Your answer is short but clear. Reinhard Reinhard Habichtsberg Dienstleistungsverantwortlicher IT-Rechenzentrum Solaris- und Datenbanksysteme Abrechnungszentrum Emmendingen > Von: Madison Pruet [mailto:madison_pruet@yahoo.com] > No. >> >> Is it possible to avoid a SDS-Server shuts down when the Primary is stopped and restarted?
Hi Reinhard,
I wasn't sure from your original post whether administration mode (onmode -j)
would obviate the need to shut down the primary.
Regardless, looking at your requirements I wonder if SDS is the best fit for
you. The system is designed to provide high availability of the primary server
and so promoting the SDS to primary (either manually or with Connection
Manager) is the way it is intended to work. The old primary then becomes the
SDS. Doing this would still allow you to maintain continuous read operations
for your clients. Is there an objection to running the SDS and primary work
load on the same machine?
Would a HDR or perhaps even RSS server be better as a read-only slave as it
would avoid this problem?
Ben.
Hi Ben,
if onmode -j (Single User Mode) would kill all sessions at the primary but
that of informix this could be the solution. Switching back to multiuser
(onmode -m) should not stop the SDS.
I'll try it. Thank you!
Kind Regards,
Reinhard.
It will mostly depends on what is the purpose of your maintenance.
If it is for doing a VM snapshot, for exemple, you should also include a
checkpoint on your onmode (onmode -cjy". I think this is a good practice.
Hope it helps.
Best regards.
Alexandre Marini
Em 23 de nov de 2016 1:16 PM, REINHARD HABICHTSBERG
<rhabichtsberg@arz-emmendingen.de> escreveu:
Hi Ben,
if onmode -j (Single User Mode) would kill all sessions at the primary but
that of informix this could be the solution. Switching back to multiuser
(onmode -m) should not stop the SDS.
I'll try it. Thank you!
Kind Regards,
Reinhard.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.
We have to realize changes of table structures periodically. To do so we need
exclusive access to the specific tables. Most of the table are in use of
running sessions which shoud be ended during maintenance periods. Sadly there
remains lots of sessions although we announce the maintenance periods resp. we
have a recurring period all two weeks. To get rid of those sessions we restart
the primary because it needs too much time to kill the sessions individual. If
we can achieve this by switching to single user mode we hit the mark.
Regards,
Reinhard.
-----Ursprüngliche Nachricht-----
Von: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] Im Auftrag von
Alexandre Marini
Gesendet: Mittwoch, 23. November 2016 16:41
An: ids@iiug.org
Betreff: Re: Shared Disk Secondary [38206]
It will mostly depends on what is the purpose of your maintenance.
If it is for doing a VM snapshot, for exemple, you should also include a
checkpoint on your onmode (onmode -cjy". I think this is a good practice.
Hope it helps.
Best regards.
Alexandre Marini
Em 23 de nov de 2016 1:16 PM, REINHARD HABICHTSBERG
<rhabichtsberg@arz-emmendingen.de> escreveu:
Hi Ben,
if onmode -j (Single User Mode) would kill all sessions at the primary but
that of informix this could be the solution. Switching back to multiuser
(onmode -m) should not stop the SDS.
I'll try it. Thank you!
Kind Regards,
Reinhard.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.
Ok, I see.
Most cases requires only an application stop, and setting IFX_DIRTY_READ
before doing the alter(s) table(s), but each case might be singular.
if you really need to kill all sessions, that single user mode should fit
(consider applying the recommended checkpoint before altering mode. Even more
if you are doing table changes).
Best regards.
Atenciosamente,
Alexandre Marini
[http://mcsoftware.com.br/mc_conteudo/assinaturas/logoassinatura.png]
alexandre@mcsoftware.com.br<mailto:alexandre@mcsoftware.com.br>
SkypeID: blinddogms
+55 11 976-030-358<tel:+55%2011%20976-030-358> | +55 11
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________________________________
De: ids-bounces@iiug.org <ids-bounces@iiug.org> em nome de Habichtsberg,
Reinhard <RHabichtsberg@arz-emmendingen.de>
Enviado: quarta-feira, 23 de novembro de 2016 14:19:11
Para: ids@iiug.org
Assunto: AW: Shared Disk Secondary [38207]
We have to realize changes of table structures periodically. To do so we need
exclusive access to the specific tables. Most of the table are in use of
running sessions which shoud be ended during maintenance periods. Sadly there
remains lots of sessions although we announce the maintenance periods resp. we
have a recurring period all two weeks. To get rid of those sessions we restart
the primary because it needs too much time to kill the sessions individual. If
we can achieve this by switching to single user mode we hit the mark.
Regards,
Reinhard.
-----Ursprüngliche Nachricht-----
Von: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] Im Auftrag von
Alexandre Marini
Gesendet: Mittwoch, 23. November 2016 16:41
An: ids@iiug.org
Betreff: Re: Shared Disk Secondary [38206]
It will mostly depends on what is the purpose of your maintenance.
If it is for doing a VM snapshot, for exemple, you should also include a
checkpoint on your onmode (onmode -cjy". I think this is a good practice.
Hope it helps.
Best regards.
Alexandre Marini
Em 23 de nov de 2016 1:16 PM, REINHARD HABICHTSBERG
<rhabichtsberg@arz-emmendingen.de> escreveu:
Hi Ben,
if onmode -j (Single User Mode) would kill all sessions at the primary but
that of informix this could be the solution. Switching back to multiuser
(onmode -m) should not stop the SDS.
I'll try it. Thank you!
Kind Regards,
Reinhard.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.
*******************************************************************************
Forum Note: Use "Reply" to post a response in the discussion forum.