How to install and access Oracle Weblogic 12.2 in the Oracle Cloud Infrastructure

I put here the steps required to install and access Weblogic in the OCI (mostly for me in case I need to do it again 😉 ). The assumptions are:

  • you already have an account for the Oracle Cloud Infrastructure and you can access the OCI console
  • you already have a Compartment with a VCN and a subnet configured (for test purposes, a VCN created with the default values will be just fine)
  • you already have a keypair for your SSH client (id_rsa, id_rsa.pub)
  • you have an X server on your laptop (if you have Windows, I recommend MobaXTerm, but Xming or other servers are just fine)

Create the compute instance

  • Menu -> Core Infrastructure -> Compute -> Instances -> Create Instance
  • Choose a name for the Instance, all the other fields defaults are fine for test (Oracle Linux 7.6, VM.Standard2.1, etc.)
  • Paste your SSH public key
  • Optionally, under advanced/network, specify a different name for the VM
  • Click on Create to complete the creation

At some point you will have an instance “Green” ready to access:

Click on it and get the public address:

Using your SSH keypair, you can now access the instance with:

 

Setup sshd for SSH tunneling and X11 forwarding

Edit as root the sshd_config:

Modify it so that the following lines are present with these values:

Those values are required for X11 forwarding (required for the graphical installation) and for SSH tunneling (required to access  the Weblogic ports without exposing them over internet).

Then restart sshd:

Install the packages for X11 

At this point, it should be possible to forward X11. You can test by reconnecting with:

and then:

Create the oracle user

At this point, you can reconnect using oracle directly, so X11 forward will work for the oracle user without any additional setup:

 

Follow the canonical steps to install weblogic

If you do not know how to do that, follow this good tutorial by Tim Hall (oracle-base):

Oracle WebLogic Server (WLS) 12cR2 (12.2.1) Installation on Oracle Linux 6 and 7

 

Access the Weblogic console from outside Oracle Cloud

If you configured correctly sshd, once the Oracle Weblogic instance is configured and started, you can tunnel to the port (it should be 7001):

And be able to browse from your laptop using localhost:7001:

HTH

Ludovico

Converting SQL*Plus calls in shell scripts to ORDS calls

I develop a lot of shell scripts. I would not define myself an old dinosaur that keeps avoiding python or other modern languages. It is just that most of my scripts automate OS commands that I would normally run interactively in an interactive shell… tar, cp, expdp, rman, dgmgrl, etc… and of course, some SQL*Plus executions.

For database calls, the shell is not appropriate: no drivers, no connection, no statement, no resultset… that’s why I need to make SQL*Plus executions (with some hacks to make them work correctly), and that’s also why I normally use python or perl for data-related tasks.

Using SQL*Plus in shell scripts

For SQL*Plus executions within a shell scripts there are some hacks, as I have said, that allow to get the data correctly.

As example, let’s use this table (that you might have found in my recent posts):

In order to get, as example, the result of this query:

and assign the values to some variables (in a shell loop), it is common to do something like this:

As you can see, there are several hacks:

  • The credentials must be defined somewhere (I recommend putting them in a wallet)
  • All the output goes in a variable (or looping directly)
  • SQL*Plus formatting can be a problem (both sqlplus settings and concatenating fields)
  • Loop and get, for each line, the variables (using awk in my case)

It is not rock solid (unexpected data might compromise the results) and there are dependencies (sqlplus binary, credentials, etc.). But for many simple tasks, that’s more than enough.

Here’s the output:

 

Using ORDS instead

Recently I have come across a situation where I had no Oracle binaries but needed to get some data from a table. That is often a situation where I use python or perl, but even in these cases, I need compatible software and drivers!

So I used ORDS instead (that by chance, was already configured for the databases I wanted to query), and used curl and jq to get the data in the shell script.

First, I have defined the service in the database:

At this point, a direct call gives this:

How to parse the data?

jq is a command-line JSON processor that can be used in a pipeline.

I can get the items:

And I can produce a csv output:

But the best, is the shell formatter, that returns strings properly escaped for usage in shell commands:

At this point, the call to eval is a natural step 🙂

The output:

😉

Ludovico

How to collect Oracle Application Server performance data with DMS and RRDtool

RRDize everything, chapter 1

If you are managing some Application Server deployments you should have wondered how to check and collect performance data.
As stated in documentation, you can gather performance metrics with the dmstool utility.
AFAIK, this can be done from 9.0.2 release upwards, but i’m concerned DMS will not work on Weblogic.

Mainly, you should have an external server that acts as collector (it could be a server in the Oracle AS farm as well): copy the dms.jar library from an Oracle AS installation to your collector and use it as you would use dmstool:

There are three basilar methods to get data:

Get all metrics at once:

Get only the interesting metrics:

Get metrics included into specific DMS tables:

What youraddress:// is, it depends on the component you are trying to connect:

If you are trying to connect to the OHS (Apache), be careful to allow remote access from the collector by editing the dms.conf file.

Now that you can query dms data, you should store it somewhere.
Personally, I did a first attempt with dmstool -dump format=xml. I wrote a parser in PHP with SimpleXML extension and I did a lot of inserts into a MySQL database. After a few months the whole data collected from tens of servers was too much to be mantained…
To avoid the maintenance of a DWH-grade database I investigated and found RRDTool. Now I’m asking how could I live without it!

I then wrote a parser in awk that parse the output of the dms.jar call and invoke an rrdtool update command.
I always use dms.jar -table command. The output has always the same format:

So I written an awk file that works for me.
use it this way:

And this is the code for update_metric_rrd:

Once you have all your rrd files populated, it’s easy to script automatic reporting. You would probably want a graph with the request count served by your Apache cluster, along with its linear regression:

This is the result:
OHS request completed
OHHHHHHHHHHHH!!!! COOL!!!!

That’s all for DMS capacity planning. Stay tuned, more about rrdtool is coming!

JBoss Portal and MySQL scalability: What The…???

I found several queries running on a MySQL 5.0 database like this one:

This query is related to JBoss Portal and does a full scan on table JBP_OBJECT_NODE.

It has bad performances (>0.8 sec) with just a few records:

mysql> select count(*) from JBP_OBJECT_NODE;
+———-+
| count(*) |
+———-+
|    33461 |
+———-+

If I rewrite the query using an inner join (à la Oracle, please forgive me) instead of a subquery I get an index scan:

With 30k records the execution time falls down from 0.8 secs to 0.01 secs…
That’s NOT all! I found this open bug:

https://jira.jboss.org/jira/browse/JBPORTAL-2040

With many users registered in, the JBoss Portal Admin console tooks over a minute to show a single page…

I don’t like portals…

JBOSS Cluster isolation and multicasting

I configured two JBoss clusters in the same LAN: a production and a test environment.
I decided to configure every single cluster with a dedicate private LANs using a restricted netmask to isolate production and test connectivity, so I assigned
192.168.100.0/255.255.255.0 to test and
192.168.200.0/255.255.255.0 to production.
I configured Apache and mod_jk to loadbalance activities between cluster instances.

The page UsingMod_jk1.2WithJBoss (http://www.jboss.org/community/docs/DOC-12525) is a good tutorial to achieve this.

What problems should I expect?
JBoss uses UDP multicasting to replicate informations across cluster nodes: even if I isolate TCP traffic, JBoss will “ear” messages sent from other clusters and will log a lot of warnings like the following:

… WARN [NAKACK] […] discarded message from non-member ….

I had to change BOTH multicast ip address and port (attributes mcast_addr and mcast_port) in the following configuration files:

  • ./deploy/jboss-web-cluster.sar/META-INF/jboss-service.xml
  • ./deploy/jmx-console.war/WEB-INF/web.xml
  • ./deploy/cluster-service.xml
  • ./deploy/ejb3-clustered-sfsbcache-service.xml
  • ./deploy/ejb3-entity-cache-service.xml

Good luck!