Last activity: 10 Jan 2017 12:10 EST
Create and Add a new Pega 7.2nstance
I'm a newbie on Pega :)
I've installed Pega Platform 7.2.1 on a Linux server with Tomcat.
Right now, I need to create a new Pega instance on another server (same as the first) for cluster mode. Can you tell me if I'm must follow only steps on chapter "Setting up the application server" (Pega721_Install_Tomcat_PostgreSQL.pdf), which means:
1- configure Tomcat
2- deploy applications archives
After that, I need to add this new node by using SMA and adds this Pega instance on the Load Balancer and its done!
Looks so easy ;)
Thanks for your help
***Updated by moderator: Lochan to add Categories***
i have done the same thing for tomcat with 2 nodes and you have the right steps above.
Thanks for your answer!
I've got another question about high availibility: I've found in the document Pega721_HighAvailabilityGuide.pdf (in attachment) these lines p28:
With crash recovery enabled, the Pega 7 Platform saves the structure of the user interface and relevant work metadata to the database on
user interface events.
But when you see the chapter "Server crash recovery" (p28), they recommend to use shared storage :
Two settings are required to enable Pega 7 Platform server crash recovery:
- storage/class/passivation/rootpath must be set to shared storage that is available to all servers in the cluster.
- session/ha/crash/RecordWorkInProgress=true indicates to the Pega 7 Platform that user interface metadata will be stored to the share file system.
Do you know why we need to use shared storage instead on the database ? Thanks
NB: have you done other settings for the high availability working well (it's the first Pega platform I build and I don't have any experience on this technology) ? Thanks
Good question, in fact, for 7.2.1, if HA is enabled (as defined by the prconfig setting ' */
session/ha/Enabled' with the value of true) - the default shared storage is database and that is recommended (in general having better performance).
i think session/ha/crash/RecordWorkInProgress=true is specific to the user interfact metadata (current tab, work object id, harness information etc), which is stored in the file system.
Thanks WaikeiKwok and KevinZheng
There are two kinds of shared storage:
- database (default when ha is enabled)
What I understand it's that for better recovery when crash, we must activate session/ha/crash/RecordWorkInProgress=true and for that, we need to have a shared storage FS, no?
Yes, for the purpose of recovering user interface metadata you will need shared storage on file system.
I can't find the session/ha/Enabled setting in DSS or prconfig.xml file.
Do you know where I can configure this purpose ? Thanks
Try refer to page 19 under https://docs-previous.pega.com/pega-721-high-availability-administration-guide for the setting session/ha/Enabled.
Ok, thanks. It's noticed that this is set to true. But I can't find the setting in DASS...
NB: is it DSS and DASS the same ? Thanks
They are the same thing. Dynamic System Setting belongs to class Data-Admin-System-Settings (DASS).
Ok, thanks WaikeiKwok.
But where can I find the setting session/ha/Enabled ? Thanks
UP. Someone can answer to my question please ? Thanks
You would need to add it in, I don't believe it is there by default.
In prconfig you would add:
<env name="session/ha/Enabled" value="true" />
Or, if you make a DSS instead...
Owning RuleSet: Pega-Engine
Thanks but I don't really understand because you can find in p19 on Pega721_HighAvailabilityGuide.pdf document:
Configuring high availability landing page visibility
You can display or hide high availability landing pages by adjusting the following prconfig setting.
l Value Type — Boolean
l Value — true or false
l Functionality — Switch to turn on or off the landing page user interface (UI)
l High availability aspect
l When the Pega 7 Platform is installed, this is set to true.
l Administrators must choose to use landing pages, AES, a NOC, SMA, or MBeans to manage
Pega 7.2.1 High Availability Administration User Guide 19
l Landing pages:
l Are not recommended due to latency of system pulse communication
l Are useful for testing purposes or Pega 7 Platform installations that do not have
Network Operations Centers
l Can be set through DASS — Yes
l Example: <env name="session/ha/Enabled" value="true" />
Looks like this setting only use for HA landing page visibility, no?
Sorry, I was answering your question "But where can I find the setting session/ha/Enabled ?" It is not present in prconfig.xml by default, but appearently it defaults to true.
What exactly are you looking for at this time?
My question is on session/ha/enabled setting: is it used for enable high availability or, like say in HA document: only to turn on or off the landing page user interface (UI) ?
As far as I can tell, that setting is only used to turn the landing page on and off for users with the correct role to see them.
Some testing I did showed that turning this off in prconfig.xml made no change. It needs to be a DSS with the following values:
Owning RuleSet: Pega-Engine
Thanks NickLoving: I haven't seen your answer ;)