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More RAM please?

SERVERThis is not a difficult question, most will say the more the merrier. YES! In theory, more RAM helped to “speed” things up. The questions are what kind of applications? And by how much?

On a VPS or dedicated server, you can buy more RAM or some called it ‘memory’ somehow to improve performance but you are buying, they aren’t free. When you add RAM, do you know the limitation of the OS? The applications? Addin more RAM to a 32bit OS, might not improve the situation. Because there is a limitation on the OS.

However, if you have a database has a lot of transaction, more RAM will help. But if the database is simply serving web content and does not have much transactions or updates. Anything at 4Gb is probably enough.

Here is my point, understand the server’s performance is relatively important. Paying more to buy more RAM every month might not solve your problem. On the other hand, should you pay more to buy more RAM to get rid of the bottleneck?

Actually, it is a debatable question, on many occasions, it is the ‘feel’ that counts. Metrix on performance are usually in very detailed value like millisecond (ms). Unless the gap is big, otherwise it is difficult to tell with a pair of naked eyes. So, understand your applications. Not forgetting RAM too has different speed, a larger RAM in capacity but slower speed or a faster RAM with lesser RAM is a debatable question too. Maybe in my next discussion.

 

Do you need a web control panel?

RELAXThis question is more for the VPS and the dedicated server users. A web control panel is likely an option when you order one of these web hostings.

The popular control panels are Plesk Onyx and cPanel with WHM. cPanel can hosts unlimited domains while Plesk Onyx comes in 3 variants support up to 10, 30 and unlimited domains. And if you are a reseller or managing a lot of users for a different domain, you should order Web Pro edition and above.

This has happened to be an option when you are ordering a VPS or dedicated server. You might be saving up to $20 every month if you are not installing a licensed control panel. There are free one but they have limited functions.

In my opinion, you can do most things without a control panel. But how soon? How fast? Who is or are using? Alright, we need to find out who are the users. If your users are business users and you are reselling, you need a control panel. If you are the administrator, you can do without in these conditions;

  • Do you have the knowledge to do it? Like to create a website, mailbox or an SSL certificate.
  • Do you have the resources? Like installing a mail server or an FTP server.
  • Do you have the time? If you need to repeatedly do the same task frequently,

 

To save the money without a control panel might require you t spend more time managing websites. Unless you are confident to do it quickly and the steps are correct, otherwise a control panel makes your life easier and you can get things done quickly.

Why do you need a VPS?

Many bought VPS, thinking it is a server. But until……. Yes, someone is telling you are still sharing a server. Huh?  am I? Yes, in the web hosting market a server may cost you a few hundreds a month, a VPS may cost you as little as $10, it will make no sense if some hoster is selling a server at $10. It is never possible.

So, what is a VPS? VPS shares a server and the server is partitioned into a few VPS. Sharing resources like CPU, Memory and even operating system. Alright, it is sharing, isn’t the same as shared hosting?

Not exactly, even they are sharing a server but overheads on VPS is still higher. VPS has its own operating system, control panel and a dedicated IP. Don’t get me wrong, shared hosting user gets or an option for dedicated IP but control panel is shared for sure.

So VPS is better? It may not the case if the hoster uses an operating system like ClloudLinux they can limit the usage of resources of one user sometimes not advertised. As such, User can decide to choose a VPS with greater resources for better performance. But if the hoster is not doing this, and the server is not overpopulated, shared hosting can be a better performance than a VPS.  A shared user can consume what is available since there is no limitation.

Thus CloudLinux is a popular choice to hosting providers sell Shared Hosting because it will throttle your usage as soon as you hit the limit.

Another reason is dedicated IP is available out of the box for VPS, there is no additional cost. So, you are sharing the same IP address with others especially good for outgoing email because of RBL.

Resell web hosting space is also the reason of buy VPS, instead of a few shared hosting accounts, you can administrate your own customers, their control panel accounts, FTP accounts etc.

Most VPS has the greater room of expansion. You can upgrade the resources like RAM, CPU or disk place and some even let you choose between SSD or the conventional hard drive.

I personally like VPS for its flexibility. I move an instance often, thus portability is important. Currently, our VPS offers this and it is easy to back things up or roll back especially they are your Sandbox.   Basically, I use them for my own reason. How about you?

Virtualize or not virtualize

VPSEver since there is virtualization especially these few years, your IT team might have been bothered by this question. To virtualize a server or….? The answer is depending. Depends on? Clearly, there are more advantages to virtualize; example license of the software is cheaper, you can install more than one instances on the same server, a virtual switch, it is portable etc.

However, there are a few things to consider that virtualization might not work for you. If you need to split the instances for different departments and it has total privacy. Virtualization does not give you true isolation, there is risk your virtualized server is accessible through the underlying virtualization OS.

Disk IO is started to divide with the number of guest machines you have deployed. The greater the number of guest machines, the slower the disk IO. If you are still using hard disk storage, this is a crucial factor for the SQL database to some.

Failure risk – if your server has failed due to hardware, you might have more than one servers are failed if you virtualized. Especially to those do not have spare resources or a virtualized cluster. Not for dedicated servers, if one failed, the rest will continue to work.

If your guest machines are not paravirtualized, there is a performance overhead, For example, a true hardware ethernet will perform 2 ~4% better than a virtualized network card.

Some software makers have realized they are missing the virtualization segment and have made changes from processor count to core count license but the end of the day virtualization will save you money if you environment permit you to do do.

 

 

Choosing the type of VPS

Basically, there is 2 type of VPS whether it is a VM, virtual machine or a VPS, they are virtualized. But if you are examing carefully, they could be different. The VPS is either virtualized by OpenVZ or the commercial licensed Virtuozzo, or Hypervisor like KVM. OpenVZ and Virtuozzo are the same types of virtualization. They are known as OS level virtualization while Hypervisor like KVM is a hardware level virtualization. In terms of usage, they are little differences but there are some restriction on an OS level virtualized environment as well as a con in like KVM full virtualization.

Let us begin,  the OpenVZ virtualization is like sharing CPU, memory and disk space dynamically. Although you are still catered to the resources you have purchased. Another word, you might use more if the server allowed but on other hands, you can be slower if your server has a lot of guest machines.  Many circumstances, an OS or a control panel files are shared using the template system. This is an advantage to the hoster, as this has greatly reduced the disk space used. And it has helped to speed up the deployment process if they are universal. You are not likely to customize it

OpenVZ uses host kernel. It’s not possible to install applications require kernel existence like Anti-Virus or Backup agent etc. However, the guest machines create instructions and make a call to the hardware directly, thus the overhead is lower and it is faster. Kernel updates might be an issue to address OS vulnerability if you do not use 3rd party solution like Kenerlcare on the host server. To take effect the changes, a reboot is required.

I prefer Hypervisor like KVM for these reasons; In a KVM guest OS is independent so the kernel. You can have a mix of OS guest machines not limited to the kind of OS installed on the host server. You can install any application, there is no such restriction like an OpenVZ VPS. No doubt KVM Full virtualization has higher overhead as their hardware is emulated and virtualization, however, these years there are improvements like ballooning and paravirtualization has improved a KVM guest machines.

If you are looking for better isolation and security. A hypervisor will do better in this area. This is one of the major reason why Vastspace has chosen KVM for our VPS plans.

Is SPF important?

SPF is a DNS record to tell other email servers that emails from the designated email servers are permitted. If emails are not originated from the mentioned email servers in the SPF, they are likely impersonated, not genuine or spam emails. At the end of the SPF statement, you will see these syntaxes – ~ ?, the common one is ~ follows by a like this ~a meaning ‘softfail’ marked the email and higher spam score if the email has violated SPF preset in the sender DNS record.

SPF is used to fight spam emails if the emails were sent from an unauthorized mail server with a probably compromised email account. It is easy to explain or interpret to a technical person. However, it is not the case for a non-tech person. For the last 20 years, I have seen many have sent emails using other email servers. These senders have more than 1 email account set in their email client application. Unknowingly, these senders sent out emails using another email server which is not authorized and eventually, the email is marked as spam or bounced.

SPF is effective to fight spam emails. But on other hands, an email can be marked as spam email mistakenly. I have mixed feeling on this. SPF set by the email server admin is used to fight spam emails, however, it can be a double-edged sword in this case. So, it is unsafe to use ‘-a’ but ‘~a’ softfail at least the email will not return in the event if the sender has used the wrong email server to send his or hers’ emails.

 

When you will need a VPS?

Many have asked the question, do I need a VPS? If you found yourselves in these situations, very likely you will need a VPS, a KVM VPS in specific.

  • I want to update my server OS kernel and reboot based on my schedule.
  • I do not want to share my services. I can restart if they are dead.
  • I want better isolation/ privacy. I do not wish to share my web content in the same environment.
  • I need one or more dedicated IP.
  • I need to root SSH to my server.

Why buy a VPS?

There are a few reasons why you should buy a VPS but not a shared Web Hosting.

  • if you want a full root shell access.
  • update a kernel fixes at your own timing (only possible with Kernel independent VPS like KVM)
  • hosts a few websites and full control with better management.
  • install the components or applications.
  • allocate unused resources.
  • restart services at your own preferences.
  • with a better budget.
  • better isolation.
  • dedicated IP address, it is optional in Shared Hosting.