How to reset the Weblogic admin server password

In some case we need to change the weblogic password, and then we can follow the below steps to reset it.

Step 1:

Set the following environment variables (update the domain name    as appropriate):

export FMW_HOME=/u01/app/oracle/product/middleware
export DOMAIN_HOME=$FMW_HOME/user_projects/domains/
export CLASSPATH=$CLASSPATH:$MW_HOME/wlserver_10.3/server/lib/weblogic.jar

NOw we will run the env as shown below.
. $DOMAIN_HOME/bin/setDomainEnv.sh

Step 2:

Need to shut down weblogic domain:
$DOMAIN_HOME/bin/stopWebLogic.sh

Step 3:

Rename and backup the DefaultAuthenticatorInit.ldift file as shown below,

cd $DOMAIN_HOME/security
mv DefaultAuthenticatorInit.ldift DefaultAuthenticatorInit.ldift.old

Now run the following command to generate a new DefaultAuthenticatorInit.ldift file. ((here ‘weblogic’ is default username))

java weblogic.security.utils.AdminAccount .

Note: Don't forget the period "." at the end of the this command, otherwise you will get "Error: Invalid arguments"

Rename and backup the following LDAP directory.

mv $DOMAIN_HOME/servers/AdminServer/data/ldap $DOMAIN_HOME/servers/AdminServer/data/ldap.old
(This ldap directory will be recreated once weblogic server startup time)

Step 4:

Back and Edit the boot.properties file and update the new password. (Above new_password)

cd $DOMAIN_HOME/servers/AdminServer/security
cp boot.properties  boot.properties_old

vi boot.properties
password=
username=

(Note: New password will be encrypted once server starts)

Step 5:

Now start your weblogic domain.

[oracle@appserver01 bin]# cd /root/MW_home/user_projects/domains/base_domain/bin/
[oracle@appserver01 bin]# ls
nodemanager  nohup.out  server_migration  service_migration  setDomainEnv.sh 
startManagedWebLogic.sh  startWebLogic.sh  stopManagedWebLogic.sh  stopWebLogic.sh
[oracle@appserver01 bin]# nohup ./startWebLogic.sh &
[oracle@appserver01 bin]# nohup: appending output to `nohup.out'
[oracle@appserver01 bin]# tail -f nohup.out 

Server state during the startup:
 
 
 
 
 
 

Now we can access your weblogic console page.

VisualVM for monitoring remote jvm

Using VisualVM we can monitor all the running Java Process and status of JDK behind these processes. VisualVM can be found inside the JDK bin directory.

By running VisualVM, by default we can access the locally run processes. To get the Remote Server processes, we have to connect with that server through credential. And in the target server, jstatd must be in running.

jstatd: 

Monitors Java Virtual Machines (JVMs) and enables remote monitoring tools to attach to JVMs. This command is experimental and unsupported. 

The jstatd command is an RMI server application that monitors for the creation and termination of instrumented Java HotSpot VMs and provides an interface to enable remote monitoring tools to attach to JVMs that are running on the local host.

To run jstatd, java security permission is required. For this purpose, at the starting of jstatd, argument will have to be passed in the command line as:

 jstatd -J-Djava.security.policy=/home/paul/jstatd.all.policy

content of jstatd.all.policy  is as:

bash-4.3$ cat /home/oracle/jstatd.all.policy

grant codebase "file:${java.home}/../lib/tools.jar" {

   permission java.security.AllPermission;

};

It permits only the min required security related permission .

NGINX: upstream timed out (110: Connection timed out) while reading response header from upstream

For my case, I got around this issue by clearing the connection keep-alive flag and specifying http version as per the answer here: 

https://stackoverflow.com/a/36589120/479632

server {
    location / {
        proxy_set_header   X-Real-IP $remote_addr;
        proxy_set_header   Host      $http_host;

        # these two lines here
        proxy_http_version 1.1;
        proxy_set_header Connection "";

        proxy_pass http://localhost:5000;
    }
}

How to kill a process on a port on ubuntu

Sometimes, when we strying to up an service and get message like: the port *** is used by another service. And we are notable to start our app to use that port. In that case, we are in need to free the port by stopping the running process. For this purpose a first we need to find out the process which is using that port.

By using the below query we can get the process id using this port:

sudo lsof -t -i:8080 [For this case 8080 is our reference port number]

to get the process in details, we can use:
ps -ef | grep


And then we can kill the process by :
kill -9

We can use the below command at once to kill the process:
sudo kill $(sudo lsof -t -i:8080)

Find and kill a process in one line using bash

For operation and other pusposes, we need to kill process in linux system. For this purpose, at first we find the process id then we kill the process with the process id. i.e

[agentrpt@localhost ~]$ ps -ef | grep 'jar'
agentrpt 13131     1  0 16:49 ?        00:00:00 java -jar ABS_ALERT_MIDDLEWARE.jar
agentrpt 13278     1  0 16:54 ?        00:00:00 java -jar SMSMailClient.jar
agentrpt 13402 13367  0 16:58 pts/0    00:00:00 grep jar

For killing process of java -jar SMSMailClient.jar, We need to executge command as:
kill 13278

We can do it in a simple way. For the using the script regulary we can create a script with the below command.

In bash, you should be able to do:

kill $(ps aux | grep '[SMS]MailClient.jar' | awk '{print $2}')

Details on its workings are as follows:

The ps gives you the list of all the processes.
The grep filters that based on your search string, [SMS] is a trick to stop you picking up the actual grep process itself.
The awk just gives you the second field of each line, which is the PID.

Remove all files/directories except for one file

find . ! -name 'filetoexist.txt' -type f -exec rm -f {} +

will remove all files except filetoexist.txt. To remove directories, change -type f to -type d and add -r option to rm.

To exclude list of files: ! \( -name one_file -o -name two_file \)

In bash, to use rm !(file.txt), we will have to enable extglob:

$ shopt -s extglob
$ rm !(file.txt)

Note that extglob only works in bash and Korn shell family. And using rm !(file.txt) can cause an Argument list too long error.

In zsh, you can use ^ to negate pattern with extendedglob enabled:

$ setopt extendedglob
$ rm ^file.txt

or using the same syntax with ksh and bash with options ksh_glob and no_bare_glob_qual enabled.

To get IP Address of Sun Server

For a normal user (i.e., not 'root') ifconfig isn't in his path, but it's the command.

More specifically: /usr/sbin/ifconfig -a

If we want the IP Address easily, we need some scripting as:

/usr/sbin/ifconfig -a | awk 'BEGIN { count=0; } { if ( $1 ~ /inet/ ) { count++; if( count==2 ) { print $2; } } }'

Modifying file using Vim and awk

In some case, we have to change a big file with the same type of text. We can use vim editor for doing this type of task. Suppose, we have a files as below:

Now for a need, we need to generate delete script from this file contents as below:

For doing so, 

1. we have opened the file using vim editor. vim loglistws.txt

2.Then we have used the below commnads to add double quate around the words : 

   :%s/EJB_Str/"EJB_Str/g

   

Then save the file using :w

   :%s/\.log/\.log"/g

3. Now save the file using :wq!

4. Now we have made a new file form the existing file as:

    cat loglistws.txt | awk '{print "rm ",$9,$10,$11,$12}' > myscriptws.sh

To run a command repeatedly in Linux

For many cases, we need to execute the command repeatedly in the shell. We can do it by cron. But in that cat its not feasible to use cron if the interval time is less than 1 min or more. Suppose, we are inclined to get the output like the top command for a specific command. We can do that in the following ways as:

watch Command
# watch free -m [By Default 2 Sec Interval]
# watch -n 10 script.sh [For the interval of 10 Seconds]
Sleep Command:
a) inside For Loop
# for i in {1..10}; do echo -n "This is a test in loop $i "; date ; sleep
b) Inside while Loop
# while true; do echo -n "This is a test of while loop";date ; sleep 5; done

Creating DB Link in Oracle Database

At first we need to add the desired database connection info in tnsnames.ora file. Usually location of tnsnames.ora file in $ORACLE_HOME/network/admin.  We will add connection info as below:

 <connection_name> =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = <db_host_name>)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = <remote_db_service_name>)
    )
  )

SARMON: nmon for Solaris

nmon (short hand for Nigel's Monitor) is a computer performance system monitor tool for the AIX and Linux operating systems developed by IBM employee Nigel Griffiths.

SARMON is for Solaris machine with the functionality of nmon.

The installation is very ease

1. Get the .zip file form Sarmon Download Link

2. Save on /var/tmp

3. Unzip the .zip

# unzip sarmon_v1.01.bin_sparc.zip

4. Make backup of original files

# cp /usr/bin/sar /usr/bin/sar.orig
# cp /usr/bin/timex /usr/bin/timex.orig
# cp /usr/lib/sa/sadc /usr/lib/sa/sadc.orig

5. Move the sarmon to /usr/local

# mv /var/tmp/sarmon_v1.01.bin_sparc /usr/local/sarmon

6. Copy files

# cp /usr/local/sarmon/sar /usr/bin/sar
# cp /usr/local/sarmon/timex /usr/bin/timex
# cp /usr/local/sarmon/sadc /usr/lib/sa/sadc

7. Edit the crontab and put the entry for collect

0 0 * * * /usr/local/sarmon/sa1 300 288 &

This start collect every day at 00:00

The files generated are in /var/adm/sa/ (day-by-day)