{"id":989,"date":"2025-11-09T14:12:42","date_gmt":"2025-11-09T14:12:42","guid":{"rendered":"https:\/\/blog.bar-solutions.com\/?p=989"},"modified":"2025-11-09T14:12:43","modified_gmt":"2025-11-09T14:12:43","slug":"keeping-the-cloud-alive-multiple-clouds","status":"publish","type":"post","link":"https:\/\/blog.bar-solutions.com\/?p=989","title":{"rendered":"Keeping the cloud alive – multiple clouds"},"content":{"rendered":"\n

I explained how I configured the Raspberry Pi and created a Python script to connect to the cloud. Now, I want to be able to keep multiple cloud databases alive using a single Raspberry Pi. In this blog, I will show you how I handled this problem.<\/strong><\/strong><\/p>\n\n\n\n

Connecting more than one cloud environment sounds impossible. After all, a new Wallet overwrites the existing one. So how can you work around this? Luckily, I already solved this issue on my laptop, using a solution that I found in this blogpost<\/a>. This is also what I did on the Raspberry Pi.<\/p>\n\n\n\n

First, I created a separate Wallet folder and moved all the files here:<\/p>\n\n\n\n

[root@rpi ~]#  cd \/usr\/lib\/oracle\/19.10\/client64\/lib\/network\/admin\/
[root@rpi admin]# mkdir Wallet_Sandbox
[root@rpi admin]# mv *.* Wallet_Sandbox\/<\/p>\n\n\n\n

Then I created another folder that consists of different Wallet files.<\/p>\n\n\n\n

[root@rpi admin]# mkdir Wallet_orcldev<\/p>\n\n\n\n

Using my FTP tool, I uploaded the files from the unzipped Wallet to this folder. To make sure that the Oracle Client can find the correct Wallet folder for the different connection strings (tnsnames entries), I created a new tnsnames.ora<\/em> file in the admin folder.<\/p>\n\n\n\n

I used tnsnames.ora<\/em> files from the Wallets and combined them into one big file. However, for this to work, I had to add a minor change to each entry.<\/p>\n\n\n\n

sandbox_low =
  (description =
     (retry_count = 20)
     (retry_delay = 3)
     (address   =
     (protocol = tcps)
     (port      = 1522)
     (host      = adb.eu-amsterdam-1.oraclecloud.com)
     )
     (connect_data = (service_name = **********_sandbox_low.adb.oraclecloud.com))
     (security =
     (MY_WALLET_DIRECTORY =
                “\/usr\/lib\/oracle\/19.10\/client64\/lib\/network\/admin\/Wallet_Sandbox”
     )
     (ssl_server_cert_dn=”CN=adb.eu-amsterdam-1.oraclecloud.com
                     ,OU=Oracle ADB AMSTERDAM,O=Oracle Corporation
                     ,L=Redwood City,ST=California,C=US”)
     )
  )<\/p>\n\n\n\n

In the security section of the entry, I told the client where to find the Wallet files. I had to do this for every entry in the tnsnames.ora file, making sure I pointed to the correct folder for the correct entry.<\/p>\n\n\n\n

Now that this part of the administration was in place, I could copy the directory with the python files. In the new directory, all I had to do was update the config.py file. Since I am using scripts to create the user, table and trigger, the password was the same. So, it was a matter of simply changing the DSN entry.<\/p>\n\n\n\n

[oracle@rpi ~]$ mkdir oradev
[oracle@rpi ~]$ cp patch72\/*.* oradev\/
[oracle@rpi ~]$ cd oradev\/
[oracle@rpi oradev]$ vi config.py
dsn = ‘orcldev_low’<\/p>\n\n\n\n

Next, I copied the shell script and altered this to call the Python script from the new folder:<\/p>\n\n\n\n

[oracle@rpi ~]$ cp keeppatchalive keeporadevalive
[oracle@rpi ~]$ vi keeporadevalive
python3 oradev\/keepalive.py<\/p>\n\n\n\n

Checked if it worked by calling the shell script:<\/p>\n\n\n\n

[oracle@rpi ~]$ .\/keeporadevalive<\/p>\n\n\n\n

To make sure this script gets called by the cron scheduler, I needed to update the crontab (while I was at it, I changed the schedule from every 5 minutes to every hour, because we know it works now):<\/p>\n\n\n\n

[oracle@rpi ~]$ crontab -e
# This command keeps the connection to patch72 alive
0 * * * * \/home\/oracle\/keeppatchalive
# This command keeps the connection to oradev alive
0 * * * * \/home\/oracle\/keeporadevalive<\/p>\n\n\n\n

<\/a>Minimizing the work<\/strong><\/strong><\/h2>\n\n\n\n

This was all pretty easy, but adding another database to the set was still a lot of work. More work than I would like to do. What if I just have to set up a user in the database that I want to keep alive, then add a couple of lines to a configuration file to point to this database? That would be a lot easier. So, with the internet as my helper, I came up with the following Python script. I decided to put procedure\/function in the same file, since I thought it was a bit of an overkill to put a single program into a single file. Maybe I am wrong. If so, please let me know in the comments.<\/p>\n\n\n\n

[KeepMeAlive.py]<\/p>\n\n\n\n

#!\/usr\/bin\/env python<\/p>\n\n\n\n

#######################################################################<\/p>\n\n\n\n

# Author : Patrick Barel –<\/p>\n\n\n\n

# Version : 0.1<\/p>\n\n\n\n

# Date : 2021-09-14<\/p>\n\n\n\n

# Filename : KeepMeAlive.py<\/p>\n\n\n\n

# Description : A python script that connects to multiple oracle<\/p>\n\n\n\n

# always free tier to keep them alive\/awake<\/p>\n\n\n\n

# Dependencies :<\/p>\n\n\n\n

#######################################################################<\/p>\n\n\n\n

import cx_Oracle<\/p>\n\n\n\n

import logging<\/p>\n\n\n\n

import json<\/p>\n\n\n\n

def connect(connection_in):<\/p>\n\n\n\n

try:<\/p>\n\n\n\n

logging.info(“Connect to %s@%s”, connection_in[“username”], connection_in[“dsn”])<\/p>\n\n\n\n

connection = cx_Oracle.connect(<\/p>\n\n\n\n

connection_in[‘username’],<\/p>\n\n\n\n

connection_in[‘password’],<\/p>\n\n\n\n

connection_in[‘dsn’],<\/p>\n\n\n\n

encoding=connection_in[‘encoding’])<\/p>\n\n\n\n

except cx_Oracle.Error as error:<\/p>\n\n\n\n

logging.error(error)<\/p>\n\n\n\n

print(error)<\/p>\n\n\n\n

finally:<\/p>\n\n\n\n

# return the connection<\/p>\n\n\n\n

if connection:<\/p>\n\n\n\n

return connection<\/p>\n\n\n\n

if __name__ == ‘__main__’:<\/p>\n\n\n\n

#######################################################################<\/p>\n\n\n\n

# start – setup logging #<\/p>\n\n\n\n

#######################################################################<\/p>\n\n\n\n

logging.basicConfig( filename=’KeepMeAlive.log’<\/p>\n\n\n\n

, level=logging.DEBUG<\/p>\n\n\n\n

, format=’%(asctime)s %(message)s’)<\/p>\n\n\n\n

logging.info(“Read the JSON file with the defined connections”)<\/p>\n\n\n\n

# Opening JSON file<\/p>\n\n\n\n

file = open(‘\/home\/oracle\/KeepMeAlive\/connections.json’,)<\/p>\n\n\n\n

# returns JSON object as<\/p>\n\n\n\n

# a dictionary<\/p>\n\n\n\n

connections = json.load(file)<\/p>\n\n\n\n

# Iterating through the json list<\/p>\n\n\n\n

logging.info(“Loop through all the defined connections”)<\/p>\n\n\n\n

for conndata in connections[‘connections’]:<\/p>\n\n\n\n

connection = connect(conndata)<\/p>\n\n\n\n

logging.info(“Close the connection (Just connecting should be enough)”)<\/p>\n\n\n\n

connection.close()<\/p>\n\n\n\n

# Closing file<\/p>\n\n\n\n

file.close()<\/p>\n\n\n\n

This program reads the connection information from a JSON file, then simply connects and disconnects to the database. However, I think just connecting should be enough to keep the databases up and running.<\/p>\n\n\n\n

The JSON file looks like this:<\/p>\n\n\n\n

[connections.json]<\/p>\n\n\n\n

{<\/p>\n\n\n\n

“connections”: [<\/p>\n\n\n\n

{ “username” : “keepalive”<\/p>\n\n\n\n

, “password” : “<aVeRySeCReTPa$$W0RD>”<\/p>\n\n\n\n

, “dsn” : “orcldev_low”<\/p>\n\n\n\n

, “port” : 1512<\/p>\n\n\n\n

, “encoding” : “UTF-8”<\/p>\n\n\n\n

}<\/p>\n\n\n\n

,<\/p>\n\n\n\n

{ “username” : “keepalive”<\/p>\n\n\n\n

, “password” : “<aVeRySeCReTPa$$W0RD>”<\/p>\n\n\n\n

, “dsn” : “sandbox_low”<\/p>\n\n\n\n

, “port” : 1512<\/p>\n\n\n\n

, \u201cencoding\u201d : \u201cUTF-8\u201d<\/p>\n\n\n\n

}<\/p>\n\n\n\n

]<\/p>\n\n\n\n

}<\/p>\n\n\n\n

I created a shell script to call this Python program:<\/p>\n\n\n\n

[oracle@rpi ~]$ cp keeporadevalive KeepDBAlive
[oracle@rpi ~]$ vi KeepDBAlive
#!\/bin\/sh
 
python3 KeepMeAlive\/KeepMeAlive.py
exit 0<\/p>\n\n\n\n

And added the following line to the crontab to add it to the cron schedule:<\/p>\n\n\n\n

[oracle@rpi ~]$ crontab -e
# This command keeps the cloud databases alive
0 * * * * \/home\/oracle\/KeepDBAlive<\/p>\n\n\n\n

If I provision a new database in the cloud, all I have to do now is create a user that can connect and adjust the connections.json<\/em> file to add the new credentials. And this program will automagically keep the new database alive. I know this code needs more error handling and better logging, but for now it works. As far as I can tell, it gets the job done and saves me (and hopefully you) time.<\/p>\n\n\n\n

<\/a>More information?<\/strong><\/strong><\/h2>\n\n\n\n

Qualogy has a lot of expertise and experience with Oracle, cloud environments and cloud databases. We are happy to share this knowledge. For more information, please contact info@qualogy.com or +31 70 319 5000.<\/p>\n\n\n\n

These articles were previously published on the Qualogy<\/a> website.<\/p>\n","protected":false},"excerpt":{"rendered":"

I explained how I configured the Raspberry Pi and created a Python script to connect to the cloud. Now, I want to be able to keep multiple cloud databases alive using a single Raspberry Pi. In this blog, I will show you how I handled this problem. Connecting more than one cloud environment sounds impossible. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28],"tags":[],"class_list":["post-989","post","type-post","status-publish","format-standard","hentry","category-keeping-the-cloud-alive"],"_links":{"self":[{"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/posts\/989","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=989"}],"version-history":[{"count":2,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/posts\/989\/revisions"}],"predecessor-version":[{"id":993,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=\/wp\/v2\/posts\/989\/revisions\/993"}],"wp:attachment":[{"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=989"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=989"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.bar-solutions.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=989"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}