AWS Transit Gateway

AWS Transit Gateway is a highly available and scalable service that provides interconnectivity between VPCs and your on-premises network. Within a Region, AWS Transit Gateway provides a method for consolidating and centrally managing routing between VPCs with a hub-and-spoke network architecture.

Between Regions, AWS Transit Gateway supports inter-regional peering with other transit gateways. It does this to facilitate routing network traffic between VPCs of different Regions over the AWS global backbone. This removes the need to route traffic over the internet. AWS Transit Gateway also integrates with hybrid network configurations when a Direct Connect or AWS Site-to-Site VPN connection is connected to the transit gateway.

AWS Transit Gateway concepts

Attachments

AWS Transit Gateway supports the following connections: 

  • One or more VPCs
  • A compatible Software-Defined Wide Area Network (SD-WAN) appliance
  • A Direct Connect gateway
  • A peering connection with another transit gateway
  • A VPN connection to a transit gateway

AWS Transit Gateway MTU

AWS Transit Gateway supports an MTU of 8,500 bytes for:

  • VPC connections
  • Direct Connect connections
  • Connections to other transit gateways
  • Peering connections

AWS Transit Gateway supports an MTU of 1,500 bytes for VPN connections.

AWS Transit Gateway route table

A transit gateway has a default route table and can optionally have additional route tables. A route table includes dynamic and static routes that decide the next hop based on the destination IP address of the packet. The target of these routes can be any transit gateway attachment. 

Associations

Each attachment is associated with exactly one route table. Each route table can be associated with zero to many attachments.

Route propagation

A VPC, VPN connection, or Direct Connect gateway can dynamically propagate routes to a transit gateway route table. With a Direct Connect attachment, the routes are propagated to a transit gateway route table by default.

With a VPC, you must create static routes to send traffic to the transit gateway.


With a VPN connection or a Direct Connect gateway, routes are propagated from the transit gateway to your on-premises router using BGP.

With a peering attachment, you must create a static route in the transit gateway route table to point to the peering attachment.

AWS Transit Gateway inter-regional peering

AWS offers two types of peering connections for routing traffic between VPCs in different Regions: VPC peering and transit gateway peering. Both peering types are one-to-one, but transit gateway peering connections have a simpler network design and more consolidated management. 

Suppose a customer has multiple VPCs in three different Regions. As the following diagram illustrates, to permit network traffic to route between each VPC requires creating 72 VPC peering connections. Each VPC needs 8 different routing configurations and security policies. 

With AWS Transit Gateway, the same environment only needs three peering connections. The transit gateway in each Region facilitates routing network traffic to all the VPCs in its Region. Because all routing can be managed by the transit gateway, the customer only needs to maintain three routing configurations, simplifying management.

Cheers

Osama

Configure AWS Command Line Interface

In this lesson i will show you how to configure AWS command line, and how to start working with your AWS account thru command line with very simple and basic steps :-

  • First of i will assume that you don’t have any user or group in your AWS console
  • from the AWS Console :-
  • From IAM ( Identity access management ) Choose Group Create Group with permission Administrator access and then hit create.
  • create user and add that user to the group in my case the group name shown above, save the secret key and access ID as CSV.
  • Now from this link here, Download AWS Command Line Interface depend on your operating system and open cmd , terminal … etc.
  • Now from Dos enter AWS configure and fill the information like the below:-
  • Open the command line and test if it’s connected to AWS now.
You can learn more about the command line from AWS documentation , if you recive the following error 
“Could not connect to the endpoint URL: “https://s3.london.amazonaws.com/”
Then make sure you are on the right Region.
Thanks
Osama

My Days As an Oracle ACED : BGOUG

12 – 14 June save the date because it’s Bulgarian Oracle User group Events, this is my first time in Bulgaria and my first time as an oracle ACE director in any events :).

My Trip Planned to be from Jordan to Bulgaria – Sofia  and as usual i need to stop in one of world airport to reach my destinations first which i really hate because it’s wasting of time and tiring me.
my stop was in Frankfurt airport and to be there i had to spent 5-6 hours in the plane to reach there and then wait another 5 hours in the airport and reach Sofia 3 hours in the plane. but lucky me the plane is delayed in Jordan and i waited for 2 hours only :).
I reach Sofia but i was really exhaust and tired from traveling because my trip started early morning and it’s took us 2 hours to reach the hotel from the airport but even with this i have to thanks one of the best organizer i ever seen Milena Gerova She organized everything very well the hotels, the taxi, the appreciation events & sessions.
I had 2 presentation there about Fusion middleware and like usual i organized RAC ATTACK On Saturday, The audience was really amazing and asking very good questions. 
I had so much fun in Bulgaria and one of the best events i attended, simply it’s really Green every where you look it’s green, and I learned some Bulgarian dance  because i knew everyone in Bulgaria should dance 🙂 Even Tom Kyte was dancing,Svetoslav and Heli as well so why not ? 
It’s really nice to meet old friends and meeting new one  🙂 

Cheers
Osama Mustafa 

Dealing with Crontab

Schedule tasks under Linux is an powerful procedure which is used by almost everyone, and to do this using program called cron. more about it here .

Procedure :

make a new text file, and enter this line in that text file like the below :-

crontab myfirstjob

Formatting crontab file :-

what this file contains

Number
Meaning
Allowed range
1
Minutes
0-59
2
Hours
0-23
3
Days
1-31
4
Months
1-12 OR First 3 letters of the Month name
5
Days of the week
0-7 OR First 3 letters of the Day name
6
Name of the program
Any program

Some useful command can be used with cron :-

Show all the task running under cron.

crontab -l

edit the crontab

crontab -e

Some example from crontab file :-

# Minute   Hour      Day of Month       Month                 Day of Week        Command  
# (0-59)     (0-23)     (1-31)             (1-12 or Jan-Dec)    (0-6 or Sun-Sat)              
    0               12           *                             *                         *            /u01/backup.sh

For more example about crontab press here

Cheers
Osama Mustafa

How to add storage to ESXI 5.5

in this post i will show you how to add New Storage to ESXI 5.5 using vsphere client follow the screenshot :-

  1. Login to Vsphere client
  2. Select the host and then choose the Configuration tab –> Storage. like below


  • Storage Type :-

  • Which Storage you want add :-
  • VMFS-3 For our case

  • Storage Name

  • maximum file size and capacity of the database.

  • Press Finish
  • Summary 

Cheers
osama mustafa

Oracle Application Adapter installation.

Regarding to Oracle Documentation :-

The Application Adapter installer for 11g Release 1 (11.1.1.3.0) is applicable for the Oracle Service-Oriented Architecture (SOA) Suite and Oracle Service Bus (OSB). The Application Adapters that are installed can be used with Business Process Execution Language (BPEL), Mediator, Business Process Management (BPM), and OSB components. Using this installer, Application Adapters can be installed in a standalone SOA environment, standalone OSB environment, or mixed (SOA and OSB) environment.

You can check from here

The installation is not that hard , it’s all about configuration. i will post about later.

You Can Download it from here.

Operating system : Oracle Linux.

Installation Steps :-

As You see you should installed Oracle SOA Or Oracle OSB.
If you are using Oracle SOA the path will be like the below :-
\Oracle_SOA1\
For Oracle OSB :-
\Oracle_OSB1\
Be Notice this application installed in the following Path :-
\Oracle_SOA1\soa\thirdparty\ApplicationAdapters\
Thank you 
Osama mustafa

ORA-01031: insufficient privileges On ASM – Grid Infrastructure 11gR2

Today like any other day started with customer call , Telling me There is problem on Grid infrastructure after restarting both node, They change heartbeat from cables to connected on switch after i told them to do this.

The Error in the logs like the  below :-
CRS-5011:Check of resource “+ASM” failed: details at “(:CLSN00006:)”

Node #2 was running without any problem , the issue was with node #1 and nothing changed recently.

The Error in Node #1 :-

crsctl start cluster

PRCR-1079 : Failed to start resource ora.asm
ORA-01031: insufficient privileges
CRS-5017: The resource action “ora.asm start” encountered the following error:
ORA-01031: insufficient privileges
. For details refer to “(:CLSN00107:)” in “/u01/app/grid/11.2.0.4/log/lux335/agent/ohasd/oraagent_oracle/oraagent_oracle.log”.

as you see from the above error “ORA-01031: insufficient privileges” i was running this command as root.
After check node #1 the solution so simple :-

Under $GRID_HOME/network/admin
vi sqlnet.ora

SQLNET.AUTHENTICATION_SERVICES = (NONE)

which is wrong and to be changed to the following value :-

SQLNET.AUTHENTICATION_SERVICES = (NTS)

Reboot Node #1 and everything running successfully.

Thank you
Osama mustafa