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Posts Tagged ‘pem’

How to register remote PEM agents to the PEM Server ?

Posted by FatDBA on April 3, 2021

Hi Guys,

During that quiesce period when I was away from blogging, I worked on lot of stuff, hence lot of contents to share 🙂 …. So here goes my another post. This one is about registering PEM agents with the PEM server as each PEM agent must be registered with the PEM server.

I have this PEM Server already configured (steps for configuring PEM server) and I have this new EDB AS 12 standby server which I would like to add to the PEM monitoring console. let’s get started! PEM Server Host (canttowin.ontadomain) Standby host (canttowinsec.quebecdomain)

I have already installed PEM agent (edb-pem-agent-8.0.1-1.rhel7.x86_64) on this remote standby host, let me show you that.

[root@canttowinsec ~]# yum install edb-pem-agent
Loaded plugins: langpacks, ulninfo
epel/x86_64/metalink | 7.0 kB 00:00:00
local | 2.9 kB 00:00:00
ol7_UEKR6 | 2.5 kB 00:00:00
ol7_latest | 2.7 kB 00:00:00
percona-release-noarch | 2.9 kB 00:00:00
percona-release-x86_64 | 2.9 kB 00:00:00
prel-release-noarch | 2.9 kB 00:00:00
Package edb-pem-agent-8.0.1-1.rhel7.x86_64 already installed and latest version
Nothing to do

Let’s go to the agent home directory and call the configuration utility called ‘pemworker’.

[root@canttowinsec bin]# pwd

[root@canttowinsec bin]# ls
pemagent pemworker pkgLauncher

Here we have to use few of the configuration options with their preferred values.
–pem-server : IP Address of the PEM backend database server.
–pem-port : Port of the PEM backend database server, default is 5432, but you have to check what port you have used.
-–pem-user : name of the Database user (having superuser privileges) of the PEM backend database server. This is a mandatory option.
–allow_server_restart: Enable the allow-server_restart parameter to allow PEM to restart the monitored server. TRUE is default.
–allow-batch-probes: Enable the allow-batch-probes parameter to allow PEM to run batch probes on this agent. FALSE is default.
-–batch-script-user: operating system user that should be used for executing the batch/shell scripts. NONE is default.

[root@canttowinsec bin]# ./pemworker --register-agent --pem-server --pem-port 5444 --pem-user enterprisedb --allow_server_restart true --allow-batch-probes true --batch-script-user enterprisedb
Postgres Enterprise Manager Agent registered successfully!

Okay, so the agent is successfully registered with the PEM Server. Next we need to add the configuration to the agent.cfg file.

[root@canttowinsec etc]# pwd
[root@canttowinsec etc]# ls

I am setting allow_streaming_replication to TRUE as this makes user to configure streaming replication, and next parameter is to provide path of CA certificates.
[root@canttowinsec etc]# echo "allow_streaming_replication=true" >> /usr/edb/pem/agent/etc/agent.cfg
[root@canttowinsec etc]# echo "ca_file=/usr/libexec/libcurl-pem/share/certs/ca-bundle.crt" >> /usr/edb/pem/agent/etc/agent.cfg

So, now my agent configuration file will look like below.

[root@canttowinsec etc]# more agent.cfg


Now you will see your PEM agent already added to the PEM agents list under PEM console.

Next you can add your standby database to the list of managed server. Here you need to follow same steps what I have discussed in my last post about PEM configuration, please click here to directly go to that post. The only difference is that you need to select the bounded agent from the drop down list, here you see your new agent coming under drop list, rest all is same!

Once it’s added successfully, you will see the new server under the list, here I have named the connection ‘EDBAS12_Sby‘.

Now here is how the main landing page will look like, new agent and database with its status.

Hope It Helped!
Prashant Dixit

Posted in Uncategorized | Tagged: , , , | Leave a Comment »

How to monitor your PostgreSQL databases using EDB PEM – Setup, Config, benchmarking and much more …

Posted by FatDBA on March 26, 2021

Hi Everyone,

Today’s post will be all about monitoring your PostgreSQL database clusters using EDB PostgreSQL Enterprise Manager (PEM). Postgres Enterprise Manager is a comprehensive, customizable solution providing an interface to control and optimize your PostgreSQL deployment.

I will be doing the installation, configuration, adding servers to the console and will perform a live monitoring of the database while I will be generating some synthetic load on the database host. I am doing this on a standalone RHEL 7 64 Bit server which I will be using it both as a PEM server and local instance. Alright, so without further ado, lets start. So, first you need to download EDB’s official repository and install following package.

Below is a complete list of packages available with name ‘edb-pem’, you need to install version: edb-pem-8.0.1-1.rhel7.x86_64

[root@canttowin repo]# yum search edb-pem
Loaded plugins: langpacks, ulninfo

=================================================================== N/S matched: edb-pem ====================================================================
edb-pem-debuginfo.x86_64 : Debug information for package edb-pem
edb-pem.x86_64 : PostgreSQL Enterprise Manager
edb-pem-agent.x86_64 : Postgres Enterprise Manager Agent
edb-pem-docs.x86_64 : Documentation for Postgres Enterprise Manager
edb-pem-server.x86_64 : PEM Server Components

Once installation is completed, go to the default installation directory, it’s /usr/edb in my case, and go to pem/bin folder.

[root@canttowin ~]# cd /usr/edb/
[root@canttowin edb]# ls
as12 bart efm-4.1 jdbc migrationtoolkit pem pgbouncer1.15 pgpool4.2
[root@canttowin ~]# cd /usr/edb/pem/bin/
[root@canttowin bin]# ls
configure-pem-server.sh configure-selinux.sh

We see two configuration shell scripts are present, we will be using the configuration script – configure-pem-server.sh
Here I will be choosing option 1 which means I will be installing web services and databases all on one host, next you need to input installation path (/usr/edb/as12 in my case), followed by super user name, port numbers and IP Address of the server.

Before I call the config script, let me quickly reset the default superuser’s password.

postgres=# alter user postgres with password 'dixit';

Now, let’s call the configuration scipt and pass all discussed values.

[root@canttowin bin]# ./configure-pem-server.sh

 EDB Postgres Enterprise Manager
Install type: 1:Web Services and Database, 2:Web Services 3: Database [ ] :1
Enter local database server installation path (i.e. /usr/edb/as12 , or /usr/pgsql-12, etc.) [ ] :/usr/edb/as12
Enter database super user name [ ] :enterprisedb
Enter database server port number [ ] :5444
Enter database super user password [ ] :
Please enter CIDR formatted network address range that agents will connect to the server from, to be added to the server's pg_hba.conf file. For example, [ ] :
Enter database systemd unit file or init script name (i.e. edb-as-12 or postgresql-12, etc.) [ ] :edb-as-12
Please specify agent certificate path (Script will attempt to create this directory, if it does not exists) [ ~/.pem/ ] :
[Info] Configuring database server.
-->  [Info] -->  [Info] Configuring database server.
-->  [Info] -->  [Info] creating role pem
-->  [Info] -->  [Info] Generating certificates
-->  [Info] -->  [Info] Executing systemctl stop edb-as-12
-->  [Info] -->  [Info] Skipping - configurations for /var/lib/edb/as12/data/pg_hba.conf and /var/lib/edb/as12/data/postgresql.conf file
-->  [Info] -->  [Info] Executing systemctl start edb-as-12
-->  [Info] -->  [Info] Enable pemagent service.
-->  [Info] -->  [Info] Executing systemctl enable pemagent
-->  [Info] -->  [Info] Stop pemagent service
-->  [Info] -->  [Info] Executing systemctl stop pemagent
-->  [Info] -->  [Info] Start pemagent service.
-->  [Info] -->  [Info] Executing systemctl start pemagent
-->  [Info] -->  [Info] Configuring httpd server
-->  [Info] -->  [Info] Executing systemctl stop httpd
-->  [Info] -->  [Info] Taking backup of /usr/edb/pem/web/pem.wsgi
-->  [Info] -->  [Info] Creating /usr/edb/pem/web/pem.wsgi
-->  [Info] -->  [Info] Taking backup of /usr/edb/pem/web/config_local.py.
-->  [Info] -->  [Info] Generating PEM Cookie Name.
-->  [Info] -->  [Info] Creating /usr/edb/pem/web/config_local.py
-->  [Info] -->  [Info] Taking backup of /etc/httpd/conf.d/edb-pem.conf
-->  [Info] -->  [Info] Creating /etc/httpd/conf.d/edb-pem.conf
-->  [Info] -->  [Info] Configuring httpd server sslconf
-->  [Info] -->  [Info] Taking backup of /etc/httpd/conf.d/edb-ssl-pem.conf
-->  [Info] -->  [Info] Taking backup of /etc/httpd/conf.d/edb-ssl-pem.conf
-->  [Info] -->  [Info] Executing /usr/edb/pem/web/setup.py
Postgres Enterprise Manager - Application Initialisation
-->  [Info] -->  [Info] Check and Configure SELinux security policy for PEM
 getenforce found, now executing 'getenforce' command
 Configure the httpd to work with the SELinux
 Allow the httpd to connect the database (httpd_can_network_connect_db = on)
 Allow the httpd to connect the network (httpd_can_network_connect = on)
 Allow the httpd to work with cgi (httpd_enable_cgi = on)
 Allow to read & write permission on the 'pem' user home directory
 SELinux policy is configured for PEM
-->  [Info] -->  [Info] Executing systemctl start httpd
-->  [Info] -->  [Info] Configured the webservice for EDB Postgres Enterprise Manager (PEM) Server on port '8443'.
-->  [Info] -->  [Info] PEM server can be accessed at at your browser

It’s completed, and at the very end it has provided URL to access the PEM GUI.

Now next step is to install PEM Agents to the server, you need to install it on all servers which you want to monitor, I am leaving the PEMAgents configuration that you do in agent.cfg file.

[root@canttowin bin]# yum install edb-pem-agent

Let’s check the PEM GUI now.

Here on the left panel you will notice there’s already one database present under ‘PEM Server Directory’ folder, this is the same database which we have configured/used PEM server, hence it will be automatically added to the server list. We will manually add one more database cluster to explain how to do it explicitly.

Let’s check the dashboard for the same (PEM Server) database for session, TPS, IO related details.

Now, let’s add another database to the monitoring console. I will be adding a community PostgreSQL 12 database to it. Go to ‘PEM Server Directory’ folder right click on it, choose option create-> server.

Next, fill connection wizard with all details i.e, username, password, IP, port and security related details for the new database and click save at the end.

And you are done!

Now, let’s see the default landing page of PEM GUI and here you see details of all added hosts and agents with their status.

Next I will create some new databases to see how that data reflects in PEM GUI.
postgres=# create database dixit;
postgres=# create database kartikey;

postgres=# \l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges | Size
dixit | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 8049 kB
kartikey | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 8049 kB
postgres | postgres | UTF8 | en_US.UTF-8 | en_US.UTF-8 | | 8193 kB

(3 rows)

All good! now let’s do some performance test to see how useful PEM can be in case of performance issues. In order to mimic or simulate the situation, I will generating some synthetic load using PostgreSQL’s default utility Pgbench.

-c number of clients
-j 2 number of threads
-t amount of transactions

These values are 10000 transactions per client. So : 10 x 10000 = 100,000 transactions

[postgres@canttowin bin]$ ./pgbench -U postgres -p 5432 -c 10 -j 2 -t 10000 postgres
starting vacuum…end.

Let’s see how the changes are captured and presented in PEM.

Okay, we can see the peaks are recorded and presented.

The load is still running and we can clearly see that from the below graph.

[postgres@canttowin bin]$ ./pgbench -U postgres -p 5432 -c 10 -j 2 -t 10000 postgres
starting vacuum…end.transaction type:
scaling factor: 1
query mode: simple
number of clients: 10
number of threads: 2
number of transactions per client: 10000
number of transactions actually processed: 100000/100000
latency average = 18.217 ms
tps = 548.940142 (including connections establishing)
tps = 548.970173 (excluding connections establishing)

Alright, so the load run has ended, let see how the graph now looks like.

So to conclude, PEM is a great tool which can fulfil all your monitoring needs, it has got some cool features too i.e. performance dashboards, tuning wizards, advisories and other graphs.

Hope It Helped
Prashant Dixit

Posted in Uncategorized | Tagged: , , , , | 1 Comment »

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