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Amazon Web Services (AWS) Blogs


How to connect two EC2 instances in AWS (Amazon Web Services)

To run a website, you need several services such as web server, database server, mail server and more.

These services need to communicate with each other to make web apps work.

But in AWS, this communication can break due to default security settings.

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How to fix Amazon AWS EC2 Connection timed out error in SMTP

Here at Bobcares, we provide Server Administration and Maintenance services to AWS account owners.

An error we sometimes see in Amazon EC2 instances is : Connection timed out error in SMTP

This is usually caused due to various reasons such as mail server security restrictions, network routing issues or even port blocks at ISP or AWS levels.

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What is Amazon EC2 Elastic IP and how to manage them efficiently

What is Amazon EC2 Elastic IP and how to manage them efficiently

AWS EC2 instances are computing services that can be used to host web services and applications. These instances belong to an Amazon virtual cloud and they can be accessed with the help of IPs in your specified range.

In our role as Outsourced Tech Support for web hosting companies, we manage Amazon EC2 instances for our customers with two types of external IPs – Public IP and Elastic IP.  (more…)

How to update PHP version in Amazon Linux to PHP 5.6

How to update PHP version in Amazon Linux to PHP 5.6

Did you know that each PHP version is fully supported only for two years from its initial stable release? Unsupported versions are vulnerable to security exploits, which is why you need to timely update PHP versions.

In the case of AWS, PHP upgrade should be performed in all server instances that run PHP, for securing them. But the upgrade steps may vary with the OS flavour in that server.
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550 Relay Not Permitted – How to fix it in Exim, cPanel, Outlook, Thunderbird and Outlook Express

550 Relay Not Permitted – How to fix it in Exim, cPanel, Outlook, Thunderbird and Outlook Express

‘550 Relay Not Permitted’ is a common error message in email programs when users attempt to send mails without proper authentication. This is a security measure to protect mail server from open relay.

In our role as Dedicated Support Specialists for web hosting companies, we see this error often reported by website owners.

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How we setup AWS disk usage monitoring for EC2 instances

How we setup AWS disk usage monitoring for EC2 instances

An EC2 instance without enough free disk space, can crash instantly. That’s why having a proper AWS disk usage monitoring system is vital for EC2 instances.

Amazon provides CloudWatch monitoring script for EC2 Linux-based instances. But it requires additional customization to make it effective for disk usage monitoring.

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Easy guide to setup Amazon EC2 multiple IPs

Easy guide to setup Amazon EC2 multiple IPs

By default, an EC2 instance comes with just a single public IP. However, there are many scenarios where you need multiple public IPs for your web services to work.

For instance, multi-site WordPress hosting, multiple websites with SSL, high availability fail-over setup for services, network appliances like load balancer, etc. require multiple IPs. (more…)

How to fix Amazon EC2 IP blacklisting in Spamhaus PBL and other email RBLs

How to fix Amazon EC2 IP blacklisting in Spamhaus PBL and other email RBLs

Amazon claims to have a system to white-list all their IP addresses at Spamhaus regularly. But we still see Amazon EC2 users reporting mail issues due to IP blacklists by Spamhaus.

IP blacklisting occur when your mail server gets compromised due to any malware or open vulnerabilities. Attackers can hijack your mail server and send spam mails from it. (more…)

AWS Port 25 block – Why does it happen and how to fix it?

AWS Port 25 block – Why does it happen and how to fix it?

From payment confirmation to support queries, emails play a vital role in online business communication. Delayed alerts or lost orders end up adversely affecting the business.

In AWS EC2 instances, mail delivery problems can happen due to many reasons, mainly port 25 connection limits, IP blacklists and port 25 blocks.

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HTTP/2 is vulnerable to DoS attacks. Here’s how to fix them.

HTTP/2 is vulnerable to DoS attacks. Here’s how to fix them.

Everyone loves fast, secure websites. Google’s SPDY and it’s successor HTTP/2 was seen as a big step towards that goal.

As of Aug 6th 2016, 9.1% of websites use HTTP/2, and the trend is seeing a steep rise. All looked good. (more…)