Email Protocols: IMAP, POP3, SMTP and HTTP

Email Protocols: IMAP, POP3, SMTP and HTTP

A protocol is about a standard method used at each end of a communication channel, in order to properly transmit information. In order to deal with your email you must use a mail client to access a mail server. The mail client and mail server can exchange information with each other using a variety of protocols.

IMAP Protocol:

IMAP (Internet Message Access Protocol) – Is a standard protocol for accessing e-mail from your local server. IMAP is a client/server protocol in which e-mail is received and held for you by your Internet server. As this requires only a small data transfer this works well even over a slow connection such as a modem. Only if you request to read a specific email message will it be downloaded from the server. You can also create and manipulate folders or mailboxes on the server, delete messages etc.

SMTP Protocol:

The SMTP (Simple Mail Transfer Protocol) protocol is used by the Mail Transfer Agent (MTA) to deliver your eMail to the recipient's mail server. The SMTP protocol can only be used to send emails, not to receive them. Depending on your network / ISP settings, you may only be able to use the SMTP protocol under certain conditions .

POP3 Protocol:

The POP (Post Office Protocol 3) protocol provides a simple, standardized way for users to access mailboxes and download messages to their computers.

When using the POP protocol all your eMail messages will be downloaded from the mail server to your local computer. You can choose to leave copies of your eMails on the server as well. The advantage is that once your messages are downloaded you can cut the internet connection and read your eMail at your leisure without incuring further communication costs. On the other hand you might have transferred a lot of message (including spam or viruses) in which you are not at all interested at this point.

HTTP Protocol:

The HTTP protocol is not a protocol dedicated for email communications, but it can be used for accessing your mailbox. Also called web based email, this protocol can be used to compose or retrieve emails from an your account. Hotmail is a good example of using HTTP as an email protocol.

Error : Shared Memory realm while opening db

Issue of Shared Memory realm faced while starting the db 11.1.0.7  installed on HP-UX 11.31

I changed the OS kernel parameter as hostname length is =8 characters so I changed the

expanded_node_host_names=1 so that hostname length will be increased from 8 -64 characters.

And did sytem restart. But while opening the database I got Shared memory realm error.

SQL> startup
Assertion failed: uname(&name) >= 0, file snlrn.c, line 395
ORA-03113: end-of-file on communication channel
SQL> shutdown immediate
ORA-01033: ORACLE initialization or shutdown in progress
SQL> startup
ORA-27100: shared memory realm already exists
HPUX-ia64 Error: 17: File exists

The uname_eoverflow kernel parameter is by default set to 1 and when I changed the expanded_node_host_names value to 1 we started facing the above issue.

If anyone takes a first look on this error, it seems that there is still shared memory occupied by previous Oracle Sessions and try to clean it up using ipcs and ipcrm commands.

uname_eoverflow: The setting of this boolean parameter determines what happens when uname gets a long hostname (and it isn't set up for long hostnames). If this kernel tunable is true (1), then generate an error EOVERFLOW; if the tunable is false (0), then silently truncate the host name before returning it in the uname system call.

expanded_node_host_names: The setting of this boolean parameter affects whether long host names (and node names) are supported. If this tunable is set to true (1), then the host and node names can be up to 255 characters (actually, 255 bytes); if set to false (0), then the limits are 8 bytes and 64 bytes for the host and node names respectively. The actual current host name (or node name) is unaffected, no matter the setting.

If both parameter values will be 1 then they will conflict each other and it will create issue to resolve HOSTNAME, which in our case was happening.

So afterwards when we changed the parameter value of uname_eoverflow to 0, above issue resolved and our database and application started smoothly.

Create Tar file and unpacking of Tar File.

Create TAR File

$ tar -cvf archivename.tar name_of_file

     v - provides a descriptuion of archived contents (optional)

     c - to create an archive

     f -  to specify a name for the archive

     archivename.tar -- name given to the archive

     name_of_file    -- name of folder or directory to be archived.

e.g tar -cvf tech_st.tar tech_st

Unpacking the TAR File

 $ tar -xvf archivename.tar

      v - provides the contents of the unpacked files

      x - to extract files

      f - designate the archive containing the files.

      arhivename.tar - the name of the archive to retrieve.

  e.g $ tar -xvf tech_st.tar

Create zipped tar ball

     # tar -cvf temp.tar tmp

     # /usr/contrb/bin/gzip temp.tar

     This creates temp.tar.gz

      You can then copy to any directory you want.

 To Uncompress zipped tar ball

     # cd /directory_you_want

     # /usr/contrib/bin/gunzip temp.tar.gz

     # tar -xvf temp.tar

     # ll tmp

Replace the default branding shown as E-Business Suite on homepage in R12 with a custom text

Replace the default branding (E-Business Suite) on homepage in R12 with a custom text

1. Login with system administrator responsibility
2. Navigate: Application ---> Function
3. Query the function FWK_HOMEPAGE_BRAND
4. Replace the User Function Name with the desired text
5. Query the function OAHOMEPAGE
6. Click on tab web_html_call
    It may be set to the following :

OA.jsp?page=/oracle/apps/fnd/framework/navigate/webui/HomePG&homePage=Y

7. Change the value of web_html_call to the following

OA.jsp?page=/oracle/apps/fnd/framework/navigate/webui/HomePG&homePage=Y&OAPB=FWK_HOMEPAGE_BRAND

8. Logout, login and the change should be visible immediate 

Change the Oracle Logo that appears in the isupport Homepage to the Company logo in R12

Changing the oracle Ebusiness Suite homepage logo to company logo

The profile option "Corporate Branding Image for Oracle Applications" controls the corporate
branding image "ORACLE" displayed at the top of all OA Framework pages.
If no value is set for this profile, OA Framework renders the corporate branding image by using
the $OA_MEDIA/FNDSSCORP.gif file.

If you change the value of this profile with the name of your custom image you will see your logo
in all pages except in the login page because the "FNDSSCORP.gif " is hard coded in MainLoginPG.xml.

Hence if you want to change the corporate branding image with your own logo and thus in all pages
including the login page the simplest solution is to:

- rename the FNDSSCORP.gif file for backup
- edit the FNDSSCORP.gif with your preferred graphic software
- log out and log into the Applications
- you should see the new logo at the top of all the page (including the login page)

2nd method:

Login to Applications as System Administrator

1. Select: System Administrator > Profile - System
2. Query profile "Corporate Branding Image for Oracle Applications"
3. Change the SITE level value to the name of the xxx.gif file ( eg  my_company_logo.gif )
4. Save the change

The second action is performed on the Application server.

1. Open a telnet/PTTY session to the Application server and source Applications environment
2. Navigate to the $OA_MEDIA directory
3. Copy the image file to this directory and make sure permissions are set properly

Now clear your browser cache and access the environment. Now the new logo should be rendered.

Q? The Custom logo is displayed differently on login page and after login. The resolution changes as opposed to the Oracle logo which stays the same size -  please explain why ?

Answer :

The Corporate branding image has a size limit.

This was good for Oracle default image FNDSSCORP.gif. But for custom images this size limit
creats distortion.

In R12 only small size branding is supported

consequently you will need to reduce the size of your logo to avoid the distortion on the login page

Refer to instructions in Framework Development guide for R12 - Note 394780.1

ADD MLOCK privilege to Oracle group:

MLOCK Privilege

To allow Oracle11g to execute asynchronous I/O operations, the group that the Oracle software owner belongs to (dba) must have the MLOCK privilege. To give the dba group the MLOCK privilege:

As the root user, enter the following command:

# setprivgrp dba MLOCK

To retain the MLOCK privilege after rebooting, create the /etc/privgroup file, if it does not exist on your system, and add the following line to it:

dba MLOCK

HP-UX Server & Unix Shutdown Command.

To shut down HP-UX for power-off, you can do any of the following:

# init 0 -- (Unix or Red hat linux )

# shutdown -h -y now

To shut down and reboot HP-UX:

# init 6 -- (Unix or Red hat linux )

# reboot

# shutdown -r -y now

To shut down HP-UX to single-user mode:

# init S

# shutdown -y now

# shutdown 0

The -h option to the shutdown command halts the system completely but

will prompt you for a message to issue users. The -y option completes

the shutdown without asking you any of the questions it would normally ask.

Compile apps schema or invalid objects in database in Oracle applications R12

Check Invalid Objects:

Connect sqlplus apps/***

SQL> select count(*) from dba_objects where status=’INVALID’;

This Query will result in total number of Invalid objects in database

Three ways to compile Invalid Objects  :

1^st    From DB Tier

Login to DB Tier  as Oracle user.

Source the environment i.e. SID_hostname.env

$ cd $ORACLE_HOME/rdbms/admin

Now run utlrp.sql script this will compile invalids objects in database

        Sqlplus ‘/as sysdba’

        SQL> @ utlrp.sql   à if you are connecting sqlplus from $ORACLE_HOME/rdbms/admin.

                                       Otherwise specify full path if from another location.

         e.g

         SQL> @$ORACLE_HOME/rdbms/admin/ utlrp.sql  

          The following pl/sql block invokes UTL_RECOMP to recompile invalid objects in Database

        2^nd From Apps Tier Using adadmin

Login to apps tier as Appsuser

       $ Source the environment i.e APPSSID_hostname.env

      $ adadmin

       Reply to the prompts.

                                                AD Administration Main Menu

   --------------------------------------------------

   1.    Generate Applications Files menu

   2.    Maintain Applications Files menu

   3.    Compile/Reload Applications Database Entities menu

   4.    Maintain Applications Database Entities menu

   5.    Change Maintenance Mode

                  6.    Exit AD Administration

  Select Option 3 and press enter

Compile/Reload Applications Database Entities

   ---------------------------------------------------

   1.    Compile APPS schema

   2.    Compile menu information

   3.    Compile flexfields

   4.    Reload JAR files to database

   5.    Return to Main Menu

Select option 1. Compile APPS Schema.

Once you select option 1 it will start compiling Invalids.

 3^rd. From SQL (Individual objects)

a)      Identity Invalid Object

 “SQL> select object_name, owner, object_type from all_objects where status like ‘INVALID’ ”

b)      SQL> alter [object] [object_name] compile;

E.g select OBJECT_NAME OBJECT_TYPE from user_objects where status 'INVALID';

               compile the objects accordingly....

               ALTER PACKAGE my_package COMPILE;

               ALTER PACKAGE my_package COMPILE BODY;

               ALTER PROCEDURE my_procedure COMPILE;

               ALTER FUNCTION my_function COMPILE;

               ALTER TRIGGER my_trigger COMPILE;

               ALTER VIEW my_view COMPILE;

SQ> show err à will display errors