The Tech Bench: The Single Best Security Tip
Your server is only as secure as what you choose to serve.
Harsh words, but it needs to be said. At ServInt, we work very hard to deliver servers to our customers that are as secure as they can be. But every customization of and installation on a server creates holes in that security. It is simply the nature of the Internet and networking. If you have data to share, you must find ways for users to access that data.
Security is a balance. The most secure server is one that is powered down and not connected to the Internet. But obviously, this server is little more than an expensive brick. To be useful, clients need to customize their servers, installing various programs that serve data out to and receive data from users on the Internet. Read more
The Tech Bench: TLS/SSL Encryption for Your Website.
We’ve all logged onto websites with an https://… url. That little “s” in https designates that the connection is using TLS/SSL encryption, an added level of security when interacting with a website. The most common places to see this are on sites that collect personal information or payments, basically anything private that users wouldn’t want to escape into the world.
Secure Sockets Layer (SSL) and its cousin, Transport Layer Security (TLS), are open standards for providing secure www service (plus mail, FTP and telnet). Originally proposed by Netscape, SSL uses RSA public-key encryption for specific TCP/IP ports. SSL competes with Secure-HTTP (S-HTTP). Read more
The Tech Bench: Plesk and cPanel log location reference guides
Ever wonder where the MST looks to investigate events on your server when you submit a ticket? Knowing the locations of various log files for both cPanel and Plesk can be invaluable when trying to understand why, when or how an event occurred on your server.
Below are breakdowns of log file locations for both control panels. Be sure to check the ServInt KnowledgeBase for handy (but large) graphic representations of of both cPanel/WHM and Plesk log locations as well. Read more
The Tech Bench: A few of our favorite links
When troubleshooting client servers, there are a few sites that the ServInt MST seems to go back to again and again. Whether it’s a reference page or a testing tool, the links below are just a few of the valuable resources our MST uses on a daily basis. And if you you’ve got a favorite, we’d love to hear about it.
intoDNS.com This a great little tool that looks into the health and configuration of your DNS and suggests any needed fixes. This is a great place to start when troubleshooting DNS issues or just checking the status of your nameserver setup.
MX Toolbox This site contains a few free tools for dns, nameserver, mx and whois lookups along with a bunch of other specific lookups in their SuperTool beta.
Traceroute tutorials on exit109.com Running a traceroute is an important part of troubleshooting a slow network connection. If you’re interested in digging a little deeper into networking and your server, this page is for you. It contains a great tutorial with just about everything you always wanted to know about running a traceroute and interpreting the output.
DNSstuff.com This is another site where you can complete a WHOIS lookup, run a traceroute or find IP information.
Exim Cheatsheet If you’re interested in something a little more advanced, this is a reference some of our techs use when troubleshooting Exim mail servers.
And of course there are our own resources. We have our KnowledgeBase as well as this very blog Series, The Tech Bench. And for our customers, the ServInt Forums are a great place to look for answers that our customers have found to many tech questions.
We hope you find these links as useful as we do. But if it’s all just a little overwhelming, don’t worry, that’s what we’re here for.
Note: By including a link on the list above, ServInt is not endorsing the purchase of any paid-for service. Also, though we tend to find the above links helpful, ServInt has no control over the accuracy of any third-party content or tools.
The Tech Bench is an ongoing blog series featuring the answers to common questions the ServInt MST fields everyday. You can also find more great tech tips in the ServInt KnowledgeBase.
Running out of CPU: Troubleshooting Slow Servers and Knowing When to Upgrade
Choosing the right size server package—and choosing a package that can be scaled easily—are important decisions in any hosting purchase. Simply buying a server with enough CPU, RAM, I/O and disk space may not be enough for customers anticipating future growth or spikes in traffic. And upping the size and cost of a server package during (or even before) a traffic spike may not always be the smartest use of a company’s money and time.
A website on a fast server on a fast network is going to be fast until the server runs out of something: CPU, RAM or I/O, or something at the software resource level like inodes. The places within your hosting infrastructure where resources are depleted first are your “bottlenecks.”
But server specifications don’t cause the bottleneck. They are simply the place where a theoretical limit collides with a real-world application. The following is a list of the five areas of interaction that can lead to a slow-down in service:
Read more
The Tech Bench: Jailshell in cPanel
Jailshell is a level of shell (SSH) access that limits a user to his or her specific directory structure. Under regular SSH when users log into their servers they are taken to their home directory and can execute commands within their directory structure.
Under SSH that user can also travel to any directoy on the server and even use “ls” to get a directory listing, they just cannot open the files or interact with them. Jailshell, on the other hand, logs users into their directory structure and locks them in (much like a prison or jail cell), disallowing them from openly traversing the directory structure outside of their home.
Jailshell is easily implementable in cPanel. You can switch an account’s shell access in WHM by navigating to Manage Shell Access, under the Account Functions header. Read more
The Tech Bench: Controlling spam and mistakenly blacklisted IPs
Editor’s Note: For this week’s Tech Bench, we thought we’d share the particulars of a recent MST ticket. If you’ve ever struggled with administering email for clients over your VPS, this is one’s for you.
Recently, a customer submitted a ticket to the MST asking for help with the email on his VPS. It quickly came to the attention of our Director of Network Compliance, Mike Witty, when the customer explained that all email going through the mail delivery IP address on his server was being blocked by AOL, Gmail and AT&T.
The reason given by the email services for blocking his IP address was that it was a suspected source of spam. Yet the customer was in contact with all the users on his VPS and knew that they were not sending out spam.
The Tech Bench: The Ins and Outs of Nameservers
Nameservers are a small, but important part of your web service. They are essentially programs that translate your domain into an IP address and vice versa. They do this so that Internet users do not have to remember 32 bit IPv4 addresses such as 123.45.67.89 or 128 bit IPv6 addresses that are far longer. They instead allow us to recall and input the familiar .com domain names for all of our favorite websites.
Every domain name needs to be listed on a nameserver somewhere. There are three kinds of nameservers to choose from: nameservers run by your web host, third-party nameservers (typically, people use the nameservers run by their domain registrar if they have third-party nameservers), and private nameservers you run on your hosted server. But which to choose?
Read more
Customer Service in Hosting, Part 3: Customer Support From the Inside
As part of my role in Engineering, I’m the guy who ends up with all the next-to-impossible support requests. It may surprise you to learn that what makes these problems hard to fix often has little to do with the actual situation at hand. The biggest “technical challenge” I find is almost always insufficient data. And insufficient data usually stems from not being able to clearly understand from the customer what the problem is.
On behalf of customer support technicians everywhere, here are some tips to make sure that you always get the best possible help from your support team, in any company: Read more
The Tech Bench: File Permissions and Ownership
After last week’s discussion of PHP handlers, we thought we’d use this week’s Tech Bench to discuss the ins and outs of file permissions and ownership.
The Numbering Scheme
File permissions are often noted as a three digit number. This number is the binary shorthand used to classify the owner, group and public permissions for the file. The value farthest to the left is for the file owner, the middle value is for the group, and the value on the right is for anyone who does not fit into the owner or group and in most circumstances should be the most restricted.
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