cheat sheet

1. Kubernetes cheat sheet: https://lnkd.in/e5huKvG
2. Docker cheat sheet: https://lnkd.in/euVgEym
3. Git and GitHub cheat sheet: https://lnkd.in/eqmYz7Y
4. Ansible cheat sheet: https://lnkd.in/eUcJGfW
5. Linux command cheat sheet: https://lnkd.in/eemfYJU
6. Open Shift cheat sheet: https://lnkd.in/euUv23d
7. Helm cheat sheet: https://lnkd.in/eupFcpy
8. Jenkins cheat sheet: https://lnkd.in/eEdSkWX
Also, get familiar with Artifactory CLI: https://lnkd.in/e3QzFNd
http://www.programmersought.com/article/95082777285/. (Ansible )

How to collect the DB hung logs from Oracle Rac.

sqlplus / as sysdba
oradebug setmypid
oradebug unlimit
oradebug -g all hanganalyze 2
oradebug -g all hanganalyze 3
oradebug tracefile_name

How to collect the the java heap dump.

 
 
 You can use jmap to collect a dump of any process that is running but you must know the process ID (pid). This is the command that you can use to obtain the pid of a Tomcat process:
 
 1) ps -eaf | grep tomcat
 
 to collect the Java heap dump:

 Log in to a running Tomcat server from which you need to collect the heap dump.

 Switch to the tomcat user:
 
 2) sudo su -tomcat
 
 Browse to the jmap path.

 Run this command to collect the heap dump and write it to a file without killing the process ID:
 
  3) jmap -dump:format=b,file=cheap.bin <pid>
 
Example

[root@sukhoi ~]#/opt/java-8u102/bin/jmap -dump:format=b,file=/mnt/sukhoi/archives/testheap.bin - F <TOMCAT PID>

/opt/java-8u231/bin/jmap -dump:format=b,file=/sukhoi.bin   2153

After you collect the heap dump, send it to the development team for analysis.

How to install the JMS opatch and JMS patch for weblogic 12.2.1.3.0

Download the both the patches

p28186730_139424_Generic.zip p31535411_122130_Generic.zip

1.0) change the permission
1.1) chown -R oracle:oinstall  p28186730_139424_Generic.zip p31535411_122130_Generic.zip

2) Command to install the Opatch,Login as oracle

2.1) unzip p28186730_139424_Generic.zip
2.2) /opt/sfw/java-8u261/bin/java -jar /tmp/6880880/opatch_generic.jar -silent oracle_home=/opt/sfw/oracle/middleware

3.0) To Verifiy the Os Patch Version

3.1) /opt/sfw/oracle/middleware/OPatch/opatch version
3.2) OPatch Version: 13.9.4.2.4
     OPatch succeeded.

4.0) To update the latest patch
4.1) Create a folder PATCH_TOP in tmp and copy the file and unzip the file. WE will get 31535411.
4.2) /opt/sfw/oracle/middleware/OPatch/opatch apply /tmp/PATCH_TOP/31535411

Note: Ensure you get

Patching component oracle.java.jaxws, 12.2.1.3.0...
Patch 31535411 successfully applied.
Sub-set patch [29016089] has become inactive due to the application of a super-set patch [31535411].
Please refer to Doc ID 2161861.1 for any possible further required actions.
Log file location: /opt/sfw/oracle/middleware/cfgtoollogs/opatch/opatch2020-08-28_08-13-04AM_1.log

4.3) /opt/sfw/oracle/middleware/OPatch/opatch lsinventory  ( Verify the patch info)

How to check the Region/AD/FD/Compartmentid/Shape from the node in OCI.

Login to the node and issue the following command.

curl http://169.254.169.254/opc/v1/instance/

How to enable to local users to allow login in OCI

Add the username in the following file

Example:

cat /etc/security/access.conf

+ : gurudatta : ALL

How to install rpm using ansible.

ansible all -b -m yum -a "name=crash state=present"

imp cheat sheets

1. Kubernetes cheat sheet: https://lnkd.in/e5huKvG
2. Docker cheat sheet: https://lnkd.in/euVgEym
3. Git and GitHub cheat sheet: https://lnkd.in/eqmYz7Y
4. Ansible cheat sheet: https://lnkd.in/eUcJGfW
5. Linux command cheat sheet: https://lnkd.in/eemfYJU
6. Open Shift cheat sheet: https://lnkd.in/euUv23d
7. Helm cheat sheet: https://lnkd.in/eupFcpy
8. Jenkins cheat sheet: https://lnkd.in/eEdSkWX
9) Artifactory CLI: https://lnkd.in/e3QzFNd
http://www.programmersought.com/article/95082777285/. (Ansible )

How to compare two file using diff.

diff host1.txt host2.txt --side-by-side

How to map the physical network interface corresponds to which ethX device?

1) ifconfig -a | grep HWaddr
2) ethtool eth0 | grep Link

How to stop the puppet agent

puppet3 agent --disable "Not Required"
service puppet3 stop
chkconfig puppet3 off

puppet3 agent --disable "Not Required";service puppet3 stop;chkconfig puppet3 off

How to update the yum repository

copy the rpm to respective location

Example:
yum Install httpd, yum install createrepo
createrepo --update /var/www/html/software/rpms
yum search tomcat
if it is not working  you can try 
yum clean expire-cache ===============================> work around.
yum search tomcat
  

how to update the weblogic patch p30675853_122130.

1) Download the patch p30675853_122130_Generic.zip
2) login as oracle
3) create a folder PATCH_TOP
4) unzip -d PATCH_TOP p30675853_122130_Generic.zip
5) /opt/oracle/middleware/OPatch/opatch version
6) /opt/oracle/middleware/OPatch/opatch lsinventory

Note: Issue the following command, if there is any error kindly stop.

[oracle@sukhoi tmp]$  /opt/oracle/middleware/OPatch/opatch apply /tmp/PATCH_TOP/30675853
Oracle Interim Patch Installer version 13.9.4.2.0
Copyright (c) 2020, Oracle Corporation.  All rights reserved.
Oracle Home       : /opt/sfw/oracle/middleware
Central Inventory : /etc/oraInventory
from           : /opt/oracle/middleware/oraInst.loc
OPatch version    : 13.9.4.2.0
OUI version       : 13.9.4.0.0
Log file location : /opt/oracle/middleware/cfgtoollogs/opatch/opatch2020-02-05_04-12-24AM_1.log
OPatch detects the Middleware Home as "/opt/oracle/middleware"
Verifying environment and performing prerequisite checks...
OPatch continues with these patches:   30675853 
Do you want to proceed? [y|n]
y
User Responded with: Y
All checks passed.
Please shutdown Oracle instances running out of this ORACLE_HOME on the local system.
(Oracle Home = '/opt/oracle/middleware')
Is the local system ready for patching? [y|n]
y
User Responded with: Y
Backing up files...

How to apply the OCT CPU patch on weblogic 10.3.6.0.

Instruction to apply the CPU patch in weblogic patch 10.3.6.0

1) Down load and copy the CPU patch p30109677_1036_Generic.zip to the following location /opt/sfw/oracle/middleware/utils/bsu/cache_dir
2) unzip the same p30109677_1036_Generic.zip
3) change the directoory to the following path /opt/sfw/oracle/middleware/utils/bsu
4) Issue the following command to check the conflicting patchs ./bsu.sh -view -status=applied -prod_dir=/opt/sfw/oracle/middleware/wlserver_10.3 -verbose
5) Edit the bsu.sh script and change memory options as follows:
   MEM_ARGS="-Xms1024m -Xmx3072m"

example:
[oracle@sukhoi bsu]$ ./bsu.sh -view -status=applied -prod_dir=/opt/sfw/oracle/middleware/wlserver_10.3 -verbose
ProductName:       WebLogic Server
ProductVersion:    10.3 MP6
Components:        WebLogic Server/Core Application Server,WebLogic Server/Admi
                   nistration Console,WebLogic Server/Configuration Wizard and
                   Upgrade Framework,WebLogic Server/Web 2.0 HTTP Pub-Sub Serve
                   r,WebLogic Server/WebLogic JDBC Drivers,WebLogic Server/Thir
                   d Party JDBC Drivers,WebLogic Server/WebLogic Server Clients
                   ,WebLogic Server/WebLogic Web Server Plugins,WebLogic Server
                   /UDDI and Xquery Support,WebLogic Server/Workshop Code Compl
                   etion Support
BEAHome:           /opt/sfw/oracle/middleware
ProductHome:       /opt/sfw/oracle/middleware/wlserver_10.3
PatchSystemDir:    /opt/sfw/oracle/middleware/utils/bsu
PatchDir:          /opt/sfw/oracle/middleware/patch_wls1036
Profile:           Default
DownloadDir:       /opt/sfw/oracle/middleware/utils/bsu/cache_dir
JavaVersion:       1.6.0_29
JavaVendor:        Sun


Patch ID:          U5I2
PatchContainer:    U5I2.jar
Checksum:          1091735558
Severity:          optional
Category:          General
CR/BUG:            29204678
Restart:           true
Description:       WLS PATCH SET UPDATE 10.3.6.0.190416
WLS PATCH SET UPDATE 10
                   .3.6.0.190416

Patch ID:          BHT3
PatchContainer:    BHT3.jar
Checksum:          352598355
Severity:          optional
Category:          General
CR/BUG:            28483404
Restart:           true
Description:       WEBLOGIC SAMPLES SPU 10.3.6.0.181016
WEBLOGIC SAMPLES SPU 10
                   .3.6.0.181016

Patch ID:          IL49
PatchContainer:    IL49.jar
Checksum:          1345789832
Severity:          optional
Category:          General
CR/BUG:            29800003
Restart:           true
Description:       10.3.6.0.190416 Overlay : MERGE REQUEST ON TOP OF WLS PSU 10
                   .3.6.0.190416 FOR BUGS 29694149 29726561
Oracle WebLogic Sev
                   er overlay patch for 10.3.6.0.190416 which requires WLS 10.3
                   .6.0.190416 PSU (Patch Number: 29204678 , Patch ID :U5I2) in
                    the environment


Note: In this case we may have to remove the IL49 and U512

5) Stop the wls service
Example: /etc/init.d/wlsoif  stop
               /etc/init.d/wlsadmin stop
6) Ensure the weblogic service is stopped.
7) Command to remove the patches ./bsu.sh -remove -patchlist=IL49,U5I2 -prod_dir=/opt/sfw/oracle/middleware/wlserver_10.3/
8) Ensure there is no Conflict.
9) ./bsu.sh -install -patch_download_dir=/opt/sfw/oracle/middleware/utils/bsu/cache_dir/ -patchlist=3L3H -prod_dir=/opt/sfw/oracle/middleware/wlserver_10.3/

Note: we should get the following message.

Checking for conflicts.............
No conflict(s) detected

Installing Patch ID: 3L3H..
Result: Success

10) Once it is done reboot the node and and ensure the both the service is started.

How to check the weblogic server version.

weblogic 10.3.6

/opt/test/oracle/middleware registry.xml
grep "WebLogic Server" AdminServer.log

weblogic 12.2.1.3.0

/opt/sfw/oracle/middleware/inventory/registry.xml

/opt/sfw/oracle/middleware/OPatch

Linux Boot Sequence

.

How to install the docker on multiple hosts using ansible

- hosts: home
  tasks:
  - name: yum
    yum:
      name: "{{ item }}"
      state: present
    with_items:
    - docker

How to disable the firewall in Centos 7.X

chkconfig firewalld off
systemctl stop firewalld
sed -i 's/=enforcing/=disabled/'g /etc/sysconfig/selinux
setenforce 0

Mdadm Cheat Sheet

http://www.ducea.com/2009/03/08/mdadm-cheat-sheet/.

Command to find the Zombie process in Linux 7

ps -xal | awk '{ print $4 " " $10 " " $13 }' | sort -n