Tuesday, 13 June 2017

SSH Tunnel to AWS RDS in Private Subnet



SSH Tunnel to RDS


We needed to connect to an RDS DB in the Amazon cloud that is not publicly accessible. Normally we  would connect through an ec2 instance but as this is time consuming and gets quite annoying we looked  at setting this up so we could simply connect via
sqlplus user/pass@tns

How to implement

1. Set up the SSH Tunnel
ssh -N -L 1521:your.rds.endpoint.rds.amazonaws.com:1521 sshuser@yourserver.com
 -N   
only set up the tunnel
 -L   
set up the forwarding
 1521
that first number is the port on your local machine
your.rds.endpoint.amazonaws.com
The name of the rds endpoint
1521
the port on the remote computer
sshuser@yourserver.com
how you log in to your ec2 instance
2. Set up a new tns entry for the tunnel connection
ORACLE-AWS =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = ORCL)
    )
  )

2. Use the SSH Tunnel
sqlplus user/pass@ORACLE-AWS
This lets you connect to the remote rds instance. Note that you have to use the host here 127.0.0.1 explicitly and that it is not the host you set up earlier. This is because it is now forwarding all of the requests. That’s all.
To be clear on how the ports work, here is another example
ssh -N -L 1234:your.rds.endpoint.rds.amazonaws.com:1521 sshuser@yourserver.com
ORACLE-AWS =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 127.0.0.1)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = ORCL)
    )
  )
This states that forward from port 1234 on my computer to port 1521 on the remote instance. 

Saturday, 10 June 2017

WTF is Markdown and why you should be using it.

WTF is Markdown and why you should be using it.



I've heard of Markdown for years but not really understood it or took much notice until today.
So what is it?
If you don’t know what Markdown is, here’s the introduction from the Markdown project page:
“Markdown is a text-to-HTML conversion tool for web writers. Markdown allows you to write using an easy-to-read, easy-to-write plain text format, then convert it to structurally valid XHTML (or HTML).
Thus, ‘Markdown’ is two things: (1) a plain-text formatting syntax; and (2) a  software tool, written in Perl, that converts the plain text formatting to HTML.”
I have just had a rude awakening to perl scripting when the need to modify a script that had not been touched in over 10 years was assigned to me in work earlier this week.  With little to no comments in the code I had to just dive into the deep end and learn it on the fly.
Every cloud has a silver lining and during my research into Perl I started to understand the benefits of using Markdown.  Another project that I am currently working on for my employer and have been for the last year involves me gathering up various server specs and details for an environment that we are working on and maintaining a "Master Copy" of the names, users, Server addresses etc that are needed to navigate and support the environment.  I can read this document just fine ... however when earlier this week it was given to a non technical member of the projects team it soon became apparent that my simple text file in the bespoke layout that I am comfortable with was not fit for purpose when read by anyone other than myself.
I was faced with two options.
1. Re-write it as a standard word doc and try my best to make it user friendly.
2. Leave it as it was and answer questions on it for the rest of my life.
I didn't like either of those option so... over to Markdown
One of its key strengths is that you can use HTML in Markdown. I was quickly able to annotate my current document with Markdown and create a very user friendly version with bells and whistles galore.
To be honest I got hooked. I have spent most of today (My day off ) teaching myself as much as I could about Markdown and its capabilities. Below are examples of what I have managed to learn and implement in the last 12 hours.
Markdown is simple and easy to pick up. I would encourage one to spend a day teaching themselves the language. There are not many technologies and languages out there that you can throw a single day at and be confident with what you are doing at the end of it

Typography

Headings

Headings from h1 through h6 are constructed with a # for each level:
# h1 Heading
## h2 Heading
### h3 Heading
#### h4 Heading
##### h5 Heading
###### h6 Heading
Renders to:

h1 Heading

h2 Heading

h3 Heading

h4 Heading

h5 Heading
h6 Heading
HTML:
<h1>h1 Heading</h1>
<h2>h2 Heading</h2>
<h3>h3 Heading</h3>
<h4>h4 Heading</h4>
<h5>h5 Heading</h5>
<h6>h6 Heading</h6>
<br>
<br>
<br>

Horizontal Rules

The HTML <hr> element is for creating a “thematic break” between paragraph-level elements. In markdown, you can create a <hr> with any of the following:
  • ___: three consecutive underscores
  • ---: three consecutive dashes
  • ***: three consecutive asterisks
renders to:



<br>
<br>
<br>

Body Copy

Body copy written as normal, plain text will be wrapped with <p></p> tags in the rendered HTML.
So this body copy:
Lorem ipsum dolor sit amet, graecis denique ei vel, at duo primis mandamus. Et legere ocurreret pri, animal tacimates complectitur ad cum. Cu eum inermis inimicus efficiendi. Labore officiis his ex, soluta officiis concludaturque ei qui, vide sensibus vim ad.
renders to this HTML:
<p>Lorem ipsum dolor sit amet, graecis denique ei vel, at duo primis mandamus. Et legere ocurreret pri, animal tacimates complectitur ad cum. Cu eum inermis inimicus efficiendi. Labore officiis his ex, soluta officiis concludaturque ei qui, vide sensibus vim ad.</p>
<br>
<br>
<br>

Emphasis

Bold

For emphasizing a snippet of text with a heavier font-weight.
The following snippet of text is rendered as bold text.
**rendered as bold text**
renders to:
rendered as bold text
and this HTML
<strong>rendered as bold text</strong>

Italics

For emphasizing a snippet of text with italics.
The following snippet of text is rendered as italicized text.
_rendered as italicized text_
renders to:
rendered as italicized text
and this HTML:
<em>rendered as italicized text</em>

strikethrough

In GFM you can do strickthroughs.
~~Strike through this text.~~
Which renders to:
Strike through this text.
<br>
<br>
<br>

Blockquotes

For quoting blocks of content from another source within your document.
Add > before any text you want to quote.
Add `>` before any text you want to quote. 
Renders to:
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.
and this HTML:
<blockquote>
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>
</blockquote>
Blockquotes can also be nested:
> Donec massa lacus, ultricies a ullamcorper in, fermentum sed augue. 
Nunc augue augue, aliquam non hendrerit ac, commodo vel nisi. 
>> Sed adipiscing elit vitae augue consectetur a gravida nunc vehicula. Donec auctor 
odio non est accumsan facilisis. Aliquam id turpis in dolor tincidunt mollis ac eu diam.
>>> Donec massa lacus, ultricies a ullamcorper in, fermentum sed augue. 
Nunc augue augue, aliquam non hendrerit ac, commodo vel nisi. 
Renders to:
Donec massa lacus, ultricies a ullamcorper in, fermentum sed augue.
Nunc augue augue, aliquam non hendrerit ac, commodo vel nisi.
Sed adipiscing elit vitae augue consectetur a gravida nunc vehicula. Donec auctor
odio non est accumsan facilisis. Aliquam id turpis in dolor tincidunt mollis ac eu diam.
Donec massa lacus, ultricies a ullamcorper in, fermentum sed augue.
Nunc augue augue, aliquam non hendrerit ac, commodo vel nisi.
<br>
<br>
<br>

Lists

Unordered

A list of items in which the order of the items does not explicitly matter.
You may use any of the following symbols to denote bullets for each list item:
* valid bullet
- valid bullet
+ valid bullet
For example
+ Lorem ipsum dolor sit amet
+ Consectetur adipiscing elit
+ Integer molestie lorem at massa
+ Facilisis in pretium nisl aliquet
+ Nulla volutpat aliquam velit
  - Phasellus iaculis neque
  - Purus sodales ultricies
  - Vestibulum laoreet porttitor sem
  - Ac tristique libero volutpat at
+ Faucibus porta lacus fringilla vel
+ Aenean sit amet erat nunc
+ Eget porttitor lorem
Renders to:
  • Lorem ipsum dolor sit amet
  • Consectetur adipiscing elit
  • Integer molestie lorem at massa
  • Facilisis in pretium nisl aliquet
  • Nulla volutpat aliquam velit
    • Phasellus iaculis neque
    • Purus sodales ultricies
    • Vestibulum laoreet porttitor sem
    • Ac tristique libero volutpat at
  • Faucibus porta lacus fringilla vel
  • Aenean sit amet erat nunc
  • Eget porttitor lorem
And this HTML
<ul>
  <li>Lorem ipsum dolor sit amet</li>
  <li>Consectetur adipiscing elit</li>
  <li>Integer molestie lorem at massa</li>
  <li>Facilisis in pretium nisl aliquet</li>
  <li>Nulla volutpat aliquam velit
    <ul>
      <li>Phasellus iaculis neque</li>
      <li>Purus sodales ultricies</li>
      <li>Vestibulum laoreet porttitor sem</li>
      <li>Ac tristique libero volutpat at</li>
    </ul>
  </li>
  <li>Faucibus porta lacus fringilla vel</li>
  <li>Aenean sit amet erat nunc</li>
  <li>Eget porttitor lorem</li>
</ul>

Ordered

A list of items in which the order of items does explicitly matter.
1. Lorem ipsum dolor sit amet
2. Consectetur adipiscing elit
3. Integer molestie lorem at massa
4. Facilisis in pretium nisl aliquet
5. Nulla volutpat aliquam velit
6. Faucibus porta lacus fringilla vel
7. Aenean sit amet erat nunc
8. Eget porttitor lorem
Renders to:
  1. Lorem ipsum dolor sit amet
  2. Consectetur adipiscing elit
  3. Integer molestie lorem at massa
  4. Facilisis in pretium nisl aliquet
  5. Nulla volutpat aliquam velit
  6. Faucibus porta lacus fringilla vel
  7. Aenean sit amet erat nunc
  8. Eget porttitor lorem
And this HTML:
<ol>
  <li>Lorem ipsum dolor sit amet</li>
  <li>Consectetur adipiscing elit</li>
  <li>Integer molestie lorem at massa</li>
  <li>Facilisis in pretium nisl aliquet</li>
  <li>Nulla volutpat aliquam velit</li>
  <li>Faucibus porta lacus fringilla vel</li>
  <li>Aenean sit amet erat nunc</li>
  <li>Eget porttitor lorem</li>
</ol>
TIP: If you just use 1. for each number, GitHub will automatically number each item. For example:
1. Lorem ipsum dolor sit amet
1. Consectetur adipiscing elit
1. Integer molestie lorem at massa
1. Facilisis in pretium nisl aliquet
1. Nulla volutpat aliquam velit
1. Faucibus porta lacus fringilla vel
1. Aenean sit amet erat nunc
1. Eget porttitor lorem
Renders to:
  1. Lorem ipsum dolor sit amet
  2. Consectetur adipiscing elit
  3. Integer molestie lorem at massa
  4. Facilisis in pretium nisl aliquet
  5. Nulla volutpat aliquam velit
  6. Faucibus porta lacus fringilla vel
  7. Aenean sit amet erat nunc
  8. Eget porttitor lorem
<br>
<br>
<br>

Code

Inline code

Wrap inline snippets of code with `.
For example, <section></section> should be wrapped as “inline”.
For example, `<section></section>` should be wrapped as "inline".

Indented code

Or indent several lines of code by at least four spaces, as in:
    // Some comments
    line 1 of code
    line 2 of code
    line 3 of code
// Some comments
line 1 of code
line 2 of code
line 3 of code

Block code “fences”

Use “fences” ``` to block in multiple lines of code.
<pre>
Sample text here...
</pre>
Sample text here...
HTML:
<pre>
  <p>Sample text here...</p>
</pre>

Syntax highlighting

GFM, or “GitHub Flavored Markdown” also supports syntax highlighting. To activate it, simply add the file extension of the language you want to use directly after the first code “fence”, ``` js, and syntax highlighting will automatically be applied in the rendered HTML. For example, to apply syntax highlighting to JavaScript code:
<pre>
grunt.initConfig({
  assemble: {
    options: {
      assets: 'docs/assets',
      data: 'src/data/*.{json,yml}',
      helpers: 'src/custom-helpers.js',
      partials: ['src/partials/**/*.{hbs,md}']
    },
    pages: {
      options: {
        layout: 'default.hbs'
      },
      files: {
        './': ['src/templates/pages/index.hbs']
      }
    }
  }
};
</pre>
Renders to:
grunt.initConfig({
  assemble: {
    options: {
      assets: 'docs/assets',
      data: 'src/data/*.{json,yml}',
      helpers: 'src/custom-helpers.js',
      partials: ['src/partials/**/*.{hbs,md}']
    },
    pages: {
      options: {
        layout: 'default.hbs'
      },
      files: {
        './': ['src/templates/pages/index.hbs']
      }
    }
  }
};
And this complicated HTML:
<div class="highlight"><pre><span class="nx">grunt</span><span class="p">.</span><span class="nx">initConfig</span><span class="p">({</span>
  <span class="nx">assemble</span><span class="o">:</span> <span class="p">{</span>
    <span class="nx">options</span><span class="o">:</span> <span class="p">{</span>
      <span class="nx">assets</span><span class="o">:</span> <span class="s1">'docs/assets'</span><span class="p">,</span>
      <span class="nx">data</span><span class="o">:</span> <span class="s1">'src/data/*.{json,yml}'</span><span class="p">,</span>
      <span class="nx">helpers</span><span class="o">:</span> <span class="s1">'src/custom-helpers.js'</span><span class="p">,</span>
      <span class="nx">partials</span><span class="o">:</span> <span class="p">[</span><span class="s1">'src/partials/**/*.{hbs,md}'</span><span class="p">]</span>
    <span class="p">},</span>
    <span class="nx">pages</span><span class="o">:</span> <span class="p">{</span>
      <span class="nx">options</span><span class="o">:</span> <span class="p">{</span>
        <span class="nx">layout</span><span class="o">:</span> <span class="s1">'default.hbs'</span>
      <span class="p">},</span>
      <span class="nx">files</span><span class="o">:</span> <span class="p">{</span>
        <span class="s1">'./'</span><span class="o">:</span> <span class="p">[</span><span class="s1">'src/templates/pages/index.hbs'</span><span class="p">]</span>
      <span class="p">}</span>
    <span class="p">}</span>
  <span class="p">}</span>
<span class="p">};</span>
</pre></div>
<br>
<br>
<br>

Tables

Tables are created by adding pipes as dividers between each cell, and by adding a line of dashes (also separated by bars) beneath the header. Note that the pipes do not need to be vertically aligned.
| Option | Description |
| ------ | ----------- |
| data   | path to data files to supply the data that will be passed into templates. |
| engine | engine to be used for processing templates. Handlebars is the default. |
| ext    | extension to be used for dest files. |
Renders to:
Option Description
data path to data files to supply the data that will be passed into templates.
engine engine to be used for processing templates. Handlebars is the default.
ext extension to be used for dest files.
And this HTML:
<table>
  <tr>
    <th>Option</th>
    <th>Description</th>
  </tr>
  <tr>
    <td>data</td>
    <td>path to data files to supply the data that will be passed into templates.</td>
  </tr>
  <tr>
    <td>engine</td>
    <td>engine to be used for processing templates. Handlebars is the default.</td>
  </tr>
  <tr>
    <td>ext</td>
    <td>extension to be used for dest files.</td>
  </tr>
</table>

Right aligned text

Adding a colon on the right side of the dashes below any heading will right align text for that column.
| Option | Description |
| ------:| -----------:|
| data   | path to data files to supply the data that will be passed into templates. |
| engine | engine to be used for processing templates. Handlebars is the default. |
| ext    | extension to be used for dest files. |
Option Description
data path to data files to supply the data that will be passed into templates.
engine engine to be used for processing templates. Handlebars is the default.
ext extension to be used for dest files.
<br>
<br>
<br>

Links

Basic link

[Assemble](http://google.com)
Renders to (hover over the link, there is no tooltip):
Google
HTML:
<a href="http://google.com">Google</a>

Add a title

[Upstage](https://github.com/upstage/ "Visit Upstage!")
Renders to (hover over the link, there should be a tooltip):
Upstage
HTML:
<a href="https://github.com/upstage/" title="Visit Upstage!">Upstage</a>

Named Anchors

Named anchors enable you to jump to the specified anchor point on the same page. For example, each of these chapters:
# Table of Contents
  * [Chapter 1](#chapter-1)
  * [Chapter 2](#chapter-2)
  * [Chapter 3](#chapter-3)
will jump to these sections:
## Chapter 1 <a id="chapter-1"></a>
Content for chapter one.

## Chapter 2 <a id="chapter-2"></a>
Content for chapter one.

## Chapter 3 <a id="chapter-3"></a>
Content for chapter one.
NOTE that specific placement of the anchor tag seems to be arbitrary. They are placed inline here since it seems to be unobtrusive, and it works.
<br>
<br>
<br>

Images

Images have a similar syntax to links but include a preceding exclamation point.
![StormRomance](https://goo.gl/photos/kkij7CgFf7YSXe6VA)
StormRomance
or
![Alt text](https://goo.gl/photos/AnAK9D29cayq6YP97 "Stromtroper Queen")
Alt text
Like links, Images also have a footnote style syntax
![Alt text][id]
Alt text
With a reference later in the document defining the URL location:
[id]: https://goo.gl/photos/AnAK9D29cayq6YP97  "Stromtroper Queen"

Thursday, 8 June 2017

Install SQLPLUS on Debian based systems


Install SQLPLUS on Debian based systems



SQLPLUS install on Debian


I have  often had to install the sqlplus instant client on debian based systems. Below I am sharing how I last went about this on Ubuntu 13.04 but the guide should be solid on other debian based distros.
SQLPLUS install Ubuntu 13.04 64 Bit

First download the package alien from the ubuntu repos. This will allow you to install rpm packages on debian based systems.
sudo apt-get install alien

Next head on over to the Oracle site and download the instant client packages listed below, you can download then all if you want but these 3 will give you the basics.
http://www.oracle.com/technetwork/topics/linuxx86-64soft-092277.html
Once that is done, go to your download folder and execute the following:

sudo alien -i oracle-instantclient12.1-basic*.rpm
sudo alien -i oracle-instantclient12.1-sqlplus*.rpm
sudo alien -i oracle-instantclient12.1-devel*.rpm
sudo apt-get install libaio1
sudo touch /etc/ld.so.conf.d/oracle.conf
sudo ldconfig


Now make sure everything is working by trying to establish an sqlplus session by building the TNS entry as below.
Notice that the command for using sqlplus is sqlplus64 as this is a 64bit install. You can of course alias this if you wish but out of the box it will work as below.

sqlplus64 username/password@//dbhost:1521/SID


Thats it, you should be done.
But that's never the case is it  :)

You will now find that you get the error

sqlplus64: error while loading shared libraries: libsqlplus.so: cannot open shared object file: No such file or directory


This is due to you having to set the LD_LIBRARY path variable to point at the required lib folder below.

/usr/lib/oracle/12.1/client64/lib/libsqlplus.so

To fix this issue add these system variables with the following commands:

touch ~/.bash_profile
echo export LD_LIBRARY_PATH=/usr/lib/oracle/12.1/client64/lib/ >> ~/.bash_profile
. ~/.bash_profile


Now when you run sqlplus64 you should be good to go.
If you want to create a tnsnames.ora that oracle will use to store TNS entries then create your tnsnames.ora file where you want it and reference it as an environment variable by adding the following to the ~/.profile file with the following commands.

echo export TNS_ADMIN=~/yourPathToFolderContainingTnsnames.ora >> ~/.bash_profile
. ~/.bash_profilevel*.rpm
sudo apt-get install libaio1
sudo touch /etc/ld.so.conf.d/oracle.conf
sudo ldconfig
touch ~/.bash_profile
echo export LD_LIBRARY_PATH=/usr/lib/oracle/12.1/client64/lib/ >> ~/.bash_profile
. ~/.bash_profile

Bash FTP Script Cronjob



Bash FTP Scripting


Creating a Bash FTP Script and installing as a cronjob can be a great way to move files around at scheduled intervals .


Want to move files around at set intervals? Even to internal servers sometimes the best way to accomplish this is with a bash ftp script. The below example of a bash script logs onto a remote FTP server and checks for messages before downloading them to the /home/user/ftp_in folder. It then checks the /home/user/ftp_out folder and transmits any files found there to the remote FTP server and then finally moves any sent files to /home/user/ftp_sent for archiving purposes.

#!/bin/bash
#pull and push from FTP SERVER
#change to the ftp_in directory
cd /home/user/ftp_in

ftp -niv ftp.address.to.connect.to << FTP_COMMAND
user username password
cd To_pvlogistics
mget *
mdel *
bye
FTP_COMMAND


#Change to the ftp_out directory
cd /home/user/ftp_out

ftp -niv ftp.address.to.connect.to << FTP_COMMAND
user username password
mput *.*
bye
FTP_COMMAND

mv * /home/user/ftp_sent

Saving an example of this script in a file called /home/user/ftp-script.sh it can be installed as a cronjob to run every X minutes as below. In this example it is set to run every 10 minutes.
*/10 * * * * /home/user/ftp-script.sh

FTP man pages for further reading and information on standard FTP commands and usage examples:

FTP

File Transfer Protocol
Syntax
      FTP [-options] [-s:filename] [-w:buffer] [host]

Key   
   -s:filename   Run a text file containing FTP commands.

   host          Host name or IP address of the remote host.

   -g            Disable filename wildcards.

   -n            No auto-login.

   -i            No interactive prompts during ftp.

   -v            Hide remote server responses.

   -w:buffer     Set buffer size to buffer
                 (default=4096)

   -d            Debug
 
   -a            Use any local interface when binding data connection.

http://ss64.com/bash/ftp.html

Change Message Of The Day (MOTD) Banner Amazon EC2


Change Message Of The Day (MOTD) Banner Amazon EC2


Permanently change the MOTD banner on AWS EC2 Amazon Linux



I found out the hard way that hanging the /etc/motd file on  Amazon EC2 AMI only works until the image is rebooted. I only came to this conclusion after spending considerable time updating it with custom messages on numerous servers. On reboot I was dismayed that all my time had been wasted. To be honest I nearly just left it as default. After all the MOTD messages that I had created with ASCII art (well an online generator ;-)) in order to wow my peers the next time someone had to logo on to grab a log file or bounce a service were not exactly essential for us to carry out our jobs. If there ever was a nice to have added to a system configuration after deployment then adding a MOTD banner was a great example.

After some perseverance I finally got to the bottom of it.



It is actually generated by a script at /usr/sbin/update-motd and the banner you see can be found at /etc/update-motd.d/30-banner. Turn off the update script with
$ sudo update-motd --disable
and then edit the banner at /etc/update-motd.
Simple when you know whats going on under the hood!
Amazon Elastic Cloud Computing
https://aws.amazon.com/ec2/

Oracle Datapump in AWS using Network Link


Oracle Datapump in AWS using Network Link



Using Oracle Datapump when using an Oracle RDS offering from Amazon Web Services can leave you tearing your hair out in frustration.

When using Oracle RDS in Amazon you do not have access to the data dump directory and as such can not use impdp/expdp. If you relay on moving databases around via dmp files as I do then this can cause you a serious problem..
One solution is to fall back on the good old fashioned IMP/EXP commands however there are limitations here such as not being easily able to export selective tables and not being allowed to re-map schemas when importing using IMP. There is also the need to allocate extent on any tables with zero rows to allow them to extract. Its all workable but can cause more work than its worth. For those interested in doing it this way (and it may be the only way you can due to infrastructure limitations) see the post here. Oracle EXP IMP on AWS
For those who want the full availability of datapump and be able to extract the dmp files back to a server of their choice than I will explain how in the below guide.
In this example we will use a windows 2012 instance inside the same VPC as the RDS instance in order to preform the Oracle datapump. This does not have to be the case. You could just as easily use an Oracle 11g install on a server of your choice. The main thing is that it must have access to the foreign database (the one you want to extract from).  If this server is inside the same VPC as the database then it can be easily be made accessible with a security group and stay relatively secure.
To use network_link you follow these simple steps:
1 Create a TNS entry for the foreign database in your tnsnames.ora file
2 Test with tnsping
3 Create a database link to the foreign database
4 Specify the database link as network_link in your expdp or impdp syntax

Step 1 Create TNS entry for foreign database

FOREIGN =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = xxxxxxxxxxxxxxxxxxxxxxxx.rds.amazonaws.com)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl)
)
)
.

Step 2 Use the tnsping command line utility to test connection

From the windows cmd line confirm there is connectivity with the foreign DB by running the tnsping utility.
C:\Users\Administrator>tnsping FOREIGN
TNS Ping Utility for 64-bit Windows: Version 11.2.0.1.0 - Production on 21-JAN-2016 17:07:54
Copyright (c) 1997, 2010, Oracle. All rights reserved.
Used parameter files:
D:\app\Administrator\product\11.2.0\dbhome_1\network\admin\sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = xxxxxxxxxxxxxxxxx.rds.amazonaws.com)(PORT = 1521)) (CONNECT_DATA = (SERVER
= DEDICATED) (SERVICE_NAME = orcl)))
OK (30 msec)

Step 3  Create a database link to the foreign database

Log onto the DB as system user
SQL> create database link foreign connect to scott identified by scott using 'foreign';
>Database link created.
SQL> select * from tab@foreign;
TNAME TABTYPE CLUSTERID
------------------------------ ------- ----------
test1 TABLE

Step 4  Specify the database link as network_link in your expdp or impdp syntax

Now its time to start the export using oracle datapump. Here you should be in familiar territory as far as the standard expdp arguments that you use.
C:\Users\Administrator> expdp scott/scott directory=network dumpfile=scott.dmp logfile=scott.log network_link=foreign 
This may be a little slower as it is transferring the data across a network all the more reason to put your extracting DB server in the same VPC as the RDS instance.
Just as a final note, it is also possible to simply datapump the DB between the foreign and the target databases directly without the use of a dump file.
C:\Users\Administrator>impdp scott/scott directory=network logfile=scott.log network_link=foreign

There are many tasks that as an Oracle DBA you will find are done slightly differently when using Amazons RDS Oracle offering. Please see links below for details on common tasks.
Tasks

Oracle IMP EXP Amazon Relational Database Service (RDS)

Oracle IMP EXP Amazon Relational Database Service (RDS)

Oracle IMP & EXP

Oracle imp exp. Import and export tools imp/exp are sometimes your only options when using Amazons Oracle RDS service. The reason for this is due to the file system on the database server being unavailable to you. The scenario where you would normally use impdp and expdp  to create a dumpfile and move it between servers is no longer a straight forward option. Using Oracle exp and imp has serious limitations such as the inability to remap schemas while importing along with difficult options to exclude certain tables while exporting. If you have administrator access to the Amazon environment where the database service is running and you can open up access to the database from another server then I have written a post here on Network Link Oracle AWS RDS.

However some of the environments that we work with are not owned or managed by our company and access to servers , firewall rules and load balancers is not an option. In this case we just have to get by with whats available. That's where the old school  imp and exp come in to the mix.

Using Oracle IMP EXP To Import and Extract

The first thing that needs to be done is to Allocate Extent on all existing tables in the schema prior to export. The reason for this is that when using the standard oracle imp exp tools any table found to have zero rows of data will be ignored and not added to the dmp file.
This can be done with the below command via sqlplus. The below sql statement will firstly set the pagesize to 0. This is needed to stop headers from being displayed in the output. Secondly it will spool the contents of the query to a file. The query will return the needed statement to run on all tables in order to allocate extent. Finally the spooled file will be called in order to run the allocate extent command on all tables.
set pagesize 0
spool allocate-extent.sql
SELECT 'ALTER TABLE '||table_name||' ALLOCATE EXTENT;' FROM user_tables WHERE segment_created = 'NO';
spool off
@allocate-extent.sql


To do the exp or imp you now need to run the commands on a server that is able to create a connection via tns to the database server.
When using an  ssh terminal session via a  program such as Linux terminal or Putty I recommend using the nohub option as below. The reason for this is to ensure that the command is pushed into the background as a process and is not dependant on the terminal session being open. Network issues or a time-out could kill you export before its finished.
Command to export:
nohup exp scott/password@production file=production.dmp &
Command to import:
nohup imp scott/password@production file=production.dmp &
You will not have any output returned to the screen as the job is now detached from the terminal. To see the output you can view the nohup.out file that is created in the directory from where you invoked the imp/exp command.
$ tail -f nohup.out
Oracle documentation for original Import and Export:
https://docs.oracle.com/cd/E11882_01/server.112/e22490/original_import.htm#SUTIL001
https://docs.oracle.com/cd/E11882_01/server.112/e22490/original_export.htm#SUTIL3634