Domains and Subdomains

Webhosting services are provided to a specific 2nd level domain (example.com). A third level (or subdomain) "www" domain (www.example.com) can be automatically created for this domain (by your choice in Hosting Control Panel during creating a new webhosting), as an alias (example.com and www.example.com are the same web presentation).

Subdomains

You can create an unlimited number of other subdomains on your domain (my.example.com). Nuclear.Hosting provide 3 types of subdomains which are sligthly different in usage.

1. Subdomain Vhost

Description

A subdomain is created like a standalone webhosting but its directory is located under the main domain hosting directory structure. The primary domain will have access to this subdomain directory (eg. with PHP script).

Subdomain Vhost features:

• custom folder name for subdomain
• turn on / off custom Error pages
• enable / disable "www" subdomain alias (www.sub.example.com)
• custom PHP version with custom PHP settings
• custom password protected AWStats statistics
• custom redirects
• Available for both VIP and Basic memberships

Subdomain Vhost Limitations:

• primary domain have access to subdomains data on the server (eg. within PHP script)
• is linked with primary domain

How to create

In the Hosting Control Panel navigate to Sites section and in the left-hand menu click on the Subdomain (Vhost). To create a new subdomain click on the green Add new subdomain.

2. Subdomain Alias

Description

It is like a regular 2nd level domain alias. This subdomain is not physicaly created, it is just an alias which can be redirected (HTTP 301 code) either to primary domain or another domain / URL. Also can be pointed to specific directory on your primary domain FTP account.

Subdomain Alias features:

• it is like an alias / virtual alias
• can be redirected to another domain (HTTP 301)
• can be redirected / routed to specific directory on the primary domain
• different redirection types (by mod_rewrite) like: no flag, R, L, R+L, R=301+L
• Let's Encrypt SSL Support (optinaly can be turned off for specific subdomain)
• Available for both VIP and Basic memberships

Subdomain Alias limitations:

• is linked with primary domain
• primary domain have access to subdomains data on the server (eg. within PHP script)
• no individual PHP settings or PHP versions (the same PHP version and configuration is applied like on primary domain)

How to create

In the Hosting Control Panel navigate to Sites section and in the left-hand menu click on the Subdomain for website. To create a new subdomain click on the green Add new Subdomain.

3. Standalone subdomain

Description

Standalone subdomain is like a regular webhosting for 2nd level domain. It is independent on any other domain. It is a full-featured webhosting. Standalone subdomains are available only for VIP membership users.

Standalone subdomain features:

• standalone and full-features webhosting with all features
• indenpedent of any other domain
• Let's Encrypt SSL support
• custom PHP version & configuration
• custom / dedicated FTP enviroment (no shared with any domain)
• and all regular webhosting benefits and features

Standalone subdomain limitations:

• no shared files / data / folders with primary or any other domain
• you need a free hosting slot availbe to create a standalone subdomain (within max. domains limits of your account)

How to create

The procedure is the same like when you creating a webhosting for a new 2nd level domain. In the Hosting Control Panel navigate to Sites section and in the left-hand menu click on the Website. To create a new subdomain click on the green Add new website.

Subdomains comparsion

	Subdomain Vhost	Subdomain Alias	Subdomain Standalone
SSL Let's Encrypt	✓	✓	✓
SSL Support	✓	✕	✓
Custom PHP version	✓	✕	✓
Custom PHP Configuration	✓	✕	✓
Data accesible from primary domain	✓	✓	✕
Depends on primary domain	✓	✓	✕
Custom redirects	✓	✓	✓
Full-featured webhosting	✕	✕	✓
Requires available hosting slot	✕	✕	✓

Aliases

What are domain aliases

An alias is a web server setting that assigns multiple domain names to a single virtual host in server configuration. It allows to display one web site under several domain names.

Alias can be configured in your Hosting Control Panel, under Sites section and then in the left-hand menu click on the Aliasdomain for website.

How to configure new domain alias

There is several way how to configure domain aliases with several different options regarding usage and behaviour you are expecting.

The same web presentations on different domains

You will use this option if you own different domains and you want everyone to have the same website.

Another use-case is when you have a domain pointed to another web hosting, you plan to transfer this domain to Nuclear.Hosting but with a newer website or newer content - you can dev a new version on hosting created on NH, on the original domain name without changing DNS record and just use an alias domain (or alias subdomain) to build a new version of the website and after that, you simply change DNS record of that domain.

Example: You have two domain names: example1.com and example2.com. A domain example1.com has created a web hosting with website uploaded and is considered as main domain. The same content you want to see on the example2.com without creating an another standalone hosting and duplicating all website files to there, which is unnecessary. To achieve desired behaviour you need to configure example2.com as alias for example1.com and change a coresponding DNS record for example2.com (point domain to our servers).

To configure such domain alias, navigate to your Hosting Control Panel, Sites and Aliasdomain for website, click on the Add new Aliasdomain.

Complete the form as described bellow:

• Domain enter your alias domain name
• Parent website is a target (website to show when you enter alias domain name) for your alias
• Redirect Type keep unchanged (No redirect)
• Redirect path keep empty
• Auto-Subdomain change value when you want to use wildcard-domain within your alias (*.youralias.tld) or www subdomain (www.youralias.tld) or just simple (none value) original alias domain name (name you entered into Domain field)

Now just click on the Save button.

Different web presentations on different domains on one hosting

FIXME: Toto nejde ako na CH, musi sa to nasmerovat do zlozky v "Cesta presmerovani"

Thanks to aliases, you can run several different web presentations on different domains on one hosting. This solution is suitable in a situation where creating or purchasing standalone hosting for a given domain name would be unnecessary.

In this case you can point your alias domain to existing subdomain on already hosted domain.

Example: You have hosting created for a domain example.com and another domains mydomain.net and yourdomain.org where you want to create a simple websites without creating a new standalone hosting accounts for them. To do this, you need to create an two folders on example.com FTP space, let say mydomain and yourdomain in the main /web folder. Upload your websites to those folders. Configure domain mydomain.net as an alias for example.com and configure Redirect Path to folder /mydomain/ and repeat the same for yourdomain.org but enter /yourdomain/ to Redirect Path. Configure necessary DNS records. Now when you enter mydomain.net content from example.com/mydomain will be loaded and when you enter yourdomain.org, content from example.com/yourdomain will appear.

To configure this type of domain alias navigate to your Hosting Control Panel, Sites and Aliasdomain for website, click on the Add new Aliasdomain.

Complete the form as described bellow:

• Domain enter your alias domain name
• Parent website is a target (website to show when you enter alias domain name) for your alias
• Redirect Type keep unchanged (No redirect) or choose L
• Redirect path enter folder name where website for this alias domain will be uploaded
• Auto-Subdomain change value when you want to use wildcard-domain within your alias (*.youralias.tld) or www subdomain (www.youralias.tld) or just simple (none value) original alias domain name (name you entered into Domain field)

Now just click on the Save button.

Websites & Web Hosting

Why we do not support caching servers (memcached, redis)

On our webservers we do not support caching servers like Memcached or Redis.

There is a big security problem with shared hosting and caching servers. Caching servers uses memory that is shared by all customers on the server. Then it is not such a problem to use the content of this shared memory to penetrate a foreign site.

Unfortunately, many shared hosting companies do not address this risk. But for us, safety comes first.

On the other side, the absence of caching servers support we have fast SSD/NVMe disks on all our servers. We are also able to connect for you a special RAM-Disk which is a dedicated piece of RAM memory connected as a regular directory (dedicated for you) where you can place your cache files. The advantage of this solution is that it's very similar to memcached or redis server where cached data are placed into RAM.

Web servers Geo-Locations

Nuclear.Hosting allows you to host your website in many different geo-locations. This feature is available for all VIP Memberships. Are your customers located primarily in 🇪🇺Europe or in the 🇺🇸USA? Are your traffic comes mostly from the 🇺🇸USA or from 🇪🇺Europe? Speed up your website and decrease the load time of your websites. Place your website in the location closest to your customers and visitors. In the table below you can find all our geo-location where you can create your web hosting. We continualy adding a new geo-locations.

WebServer	Geo-Location	Server Hostname	IPv4 Address	IPv6 Address
EU-FR1	🇪🇺Europe - France - Gravelines	denver.nuclearserver.xyz	87.98.254.239	2001:41d0:303:c978::100
EU-GB1	🇪🇺Europe - United Kingdom - London	london.nuclearserver.xyz	51.75.162.123	2001:41d0:801:2000::15b9
EU-DE1	🇪🇺Europe - Germany - Frankfurt	frankfurt.nuclearserver.xyz	51.195.45.175	2001:41d0:701:1100::41a
USA-US1	🇺🇸USA - Virginia - Warrenton	boston.nuclearserver.xyz	51.81.80.188	2604:2dc0:101:200::95c

Would you like to add some specific Geo-locations? Let us know!

Authorization header in HTTP request

By default, Authorization header in HTTP requests provided to webserver and your PHP applications is not present and is filtered by webserver. In situation, when you need to work with Authorization header in HTTP requests (eg. Restful API with JWT authorization and so on), you need to adjust your .htaccess file.

Open (or create) your .htaccess file under your website and add the following directive to enable Authorization header passing to your application:

CGIPassAuth on

WAF - Web Application Firewall

What is WAF

A web application firewall (WAF) is an application firewall for HTTP applications. It applies a set of rules to an HTTP conversation. By inspecting HTTP traffic, it can prevent attacks stemming from web application security flaws, such as SQL injection, cross-site scripting (XSS), file inclusion, and security misconfigurations.

On our servers we are using ModSecurity as WAF.

TTFB - Time To First Byte

Time to first byte (TTFB) is a measurement used as an indication of the responsiveness of a webserver or other network resource. TTFB measures the duration from the user or client making an HTTP request to the first byte of the page being received by the client's browser.

Time to first byte is an element of site speed, but a low TTFB on its own is not enough to make a site fast. For example, if a site has a low TTFB but lots of images, ads, javascript files, connecting to external resources (3rd party APIs) then it will still take a long time for the site to load fully.

There are three main components to TTFB:

• Request: When a web browser goes to a website, it sends an http request which gets routed and travels to eventually reach the server that hosts the site.
• Server processing: The server receives the request, pass it to your web application, your website processes it and sends back response.
• Response: The response from the server gets routed and travels back to the web browser. TTFB is the time it takes for the first piece of the response to reach the web browser.

The location of your visitors is a big factor because the request has to travel from the visitor’s computer to the server, and then the response has to travel all the way back.

For a website hosted in the US, a visitor from a US city might get a TTFB under 200 milliseconds, while a visitor from Europe could get a TTFB of 1 second or more.

The speed of the visitor’s internet is also important. A slow connection with a bad signal could have a much higher TTFB.

One of the most important elements in the TTFB is your website / your web application. The actual response to clients request is generated by your application. Webserver pass clients request to your application (either HTML or PHP). Your application process the request (for example by executing PHP code) and return some output which webserver send back to the client's browser. If your application is slow, executing of your PHP code is slower, not efficient enough, consumes too much server resources, handling a lot of data (from MySQL database or 3rd party services), the request processing will be longer and TTFB will rise essentially.

How to measure TTFB

There are several free tools you can use to measure your website’s TTFB.

1. KeyCDN Tool

This free tool from KeyCDN tests your website’s TTFB from 14 different locations around the world.

The difference in TTFB measured is mostly due to the distance from the testing locations to the web server.

2. WebPageTest

WebPageTest has a very detailed speed test tool that gives you a lot of data, including a detailed waterfall chart that shows all the different files that load.

It also gives you a result for TTFB, both an exact number and a letter grade.

3. PageSpeed Insights

TTFB is also a component of Google’s PageSpeed Insights test tool. If it is high, the tool gives you a warning and lowers your score.

4. Google Chrome DevTools / Firefox DevTools

You can measure TTFB in Google Chrome / Firefox by launching DevTools. Remember, if you are testing from your computer that TTFB is affected by network latency and your internet connection.

How to improve your TTFB

Regarding to our previous explanation of TTFB, there is a several steps you can do to improve your TTFB.

1. Optimize your web application

This is a first and mandatory step to significantly improve your TTFB. What does it mean in particular?

• analyse your SQL queries, slow queries, simplifie them
• analyse content in SQL tables, check if you are using indexes, remove old or unnecessary content from SQL tables
• analyse if your website is connecting to any 3rd party websites or APIs, check how long this connection takes, consider not to call this resource online rather than in CRON or if you have to call them, configure lowest possible timeout for this connection
• prevent loading a big images, a lot of CSS or JS files, move them to end of the page loading if possible
• use PHP profiller tool to investigate bottlenecks in your app or NewRelic tool
• consider to use caching (caching plugin if you are using CMS) to cache and serve static content and/or SQL queries

2. Keep your server as close to your users as possible

The distance from the web server is one of the most important determinants of TTFB.

If the majority of your users come from the US, then your site should be hosted in the US. If it’s a UK-specific website, then it should be hosted in the UK or Europe in general.

3. Use a content delivery network (CDN)

CDN stands for Content Delivery Network.

By using a CDN for your website, you can cache static files like images, css files and javascript files on servers that are close to your visitors. A CDN can speed up your site by serving these static files to your visitors much faster. It does not lower the TTFB of your initial html page file, but it does significantly lower the TTFB of the static files.

Popular CDN network are CloudFlare or OVH CDN.

4. Switch to a faster web host

If your web server is poorly configured or not powerful enough to deliver a speedy response to the visitor, then your TTFB will be high.

When it comes to web hosting, you really do get what you pay for. A cheap web hosting provider may be holding your site back and preventing it from reaching its full potential