In the June 2018 survey we received responses from 1,630,322,579 sites, 217,776,658 unique domains, and 7,614,764 web-facing computers. This reflects a gain of 45 million sites and 162,000 web-facing computers, but a loss of 98,800 domains.

Apache currently leads by most metrics, with the largest market share of domains (35.23%), active sites (41.13%), computers (40.28%), and top million sites (35.54%). However, it continues to gradually decline in market share, losing out to continued growth elsewhere, particularly by nginx. Most of Apache's figures fell this month, with the exception of a small 35k (+1.16%) rise in web-facing computers. Despite this gain in web-facing computers, its share fell slightly, by 0.4 percentage points.

The only metric where Apache does not retain the lead is web sites: Microsoft's server software has held the lead since July 2016. Although Microsoft web servers now account for 601 million sites, or 36.9%, relatively few of these are active sites. Microsoft servers account for 11.8 million active sites, a 6.62% share of the entire active site market, placing it behind both Apache and nginx. Internet Information Services (IIS) accounts for 97.8% of all domains using Microsoft server products, with Microsoft's light-weight HTTPAPI making up just 2.2% of Microsoft's domains. Only 8.0% of the web-facing computers running Microsoft IIS run the latest version available, IIS 10.0, released in October 2016 as part of Windows Server 2016. A greater proportion, 10.1%, are still running IIS 6.0, which reached end-of-life along with Windows Server 2003 almost 3 years ago.

nginx continues to rise in popularity, growing faster than its Apache and Microsoft competitors in all metrics except web sites. Although nginx's 23.35% domain share is still behind Microsoft's 25.73%, its continued growth has it on track to overtake Microsoft in a few months, and potentially even bring Apache within its sights in a couple of years. nginx holds second place in terms of active sites (21.64%), computers (25.84%), and the number of sites within the top one million (24.68%). This month, nginx had the largest gains in all metrics with the exception of overall web sites. Apart from its original distribution, nginx also comes in two other popular variants: Openresty, which is based on an nginx core with additional Lua-based modules, was seen on 2.0 million domains this month; and Tengine, an nginx fork maintained by Chinese ecommerce site Taobao, was seen on 1.2 million domains.

The LiteSpeed web server, which currently accounts for 1.27% of all domains, has also been slowly but steadily gaining adopters. It experienced the 3^rd largest increase in domains this month, gaining 125k, giving it a larger relative increase than Apache, Microsoft, or nginx servers. LiteSpeed has a slightly higher market share of 1.50% of the top million sites and 1.86% of all active sites.

In the February 2018 survey we received responses from 1,838,596,056 sites across 214,036,874 unique domain names and 7,290,968 web-facing computers. This reflects a gain of 63,000 computers, and nearly a million additional domains. Overall hostname growth was 33 million, and the number of active sites grew by 9.3 million.

Microsoft dominated this month's domain growth, with an extra 1.1 million domains (+2.0%) taking its market share up by 0.41 percentage points to 26.5%, while Apache lost 115,000 domains. Microsoft also saw the largest hostname growth, with an additional 59 million sites taking its leading hostname share up by 2.65 points to 34.5%.

After excelling in all growth metrics last month, nginx did not sweep the board this time. Although its computer growth continued to be strong – gaining 44,000 this month – it lost 11.2 million hostnames globally. The primary cause of this was more than 15 million sites switching from nginx to Apache. Most of these sites were previously hosted by Raksmart in China, but are now hosted by Data Foundry in the United States.

All four of the largest major vendors – Apache, nginx, Google and Microsoft – gained active sites this month. Apache made the largest gain of 2.1 million, but this was not enough to prevent its active sites share falling by 1.1 points to 42.7%. Nonetheless, Apache continues to lead with more than twice as many active sites as its closest competitor, nginx.

Cloudflare-nginx migration underway

For several years, every edge machine in Cloudflare's content delivery network (CDN) exhibited the Server: cloudflare-nginx HTTP response header. This reflected the fact that its custom software stack was based on nginx – but this month's survey saw a vast swathe of websites switching to a new Server: cloudflare header.

Although nginx remains part of Cloudflare's stack, it plays less of a role than it once did. The code that handles HTTP requests on Cloudflare's machines now goes far beyond the capabilities of nginx alone, and Cloudflare also hints that it will most likely end up writing its own caching software instead of using nginx.

In line with Cloudflare's reasoning, Netcraft's survey treats the new cloudflare server as a distinct product to nginx, and this has taken a chunk out of nginx's share in the top million sites. The new cloudflare server already accounts for 5.2% of the top million sites, and this share will undoubtedly increase next month.

The transition to the new cloudflare server banner started on 18 December 2017, and the February 2018 survey found nearly 60% of Cloudflare's sites using the new banner. It is likely that they will all use the new banner by next month's survey.

Other web server news

The developers of nginx have added support for HTTP/2 Server Push, which is likely to be made available in the next release. This feature allows web servers to send resources such as images and stylesheets before they are requested by the browser, which can make some webpages load faster.

After coming to prominence last month, DPS is now the 9th largest server by domains. It continues to be used almost exclusively by GoDaddy to host sites created with its Website Builder tool, and it is still being regularly updated. The current version in use at the time of writing is DPS 1.2.1, whereas a month ago it was 1.1.20.

OpenLiteSpeed 1.5.0 RC1 was released on 2 February, adding new Multi-Thread APIs and a module developer guide. This followed the 10 January release of 1.4.29, which is currently the latest stable version of the freely available open source server. Just over 2.5 million domains are currently using OpenLiteSpeed or the commercially available LiteSpeed Web Server product. Both products use the same LiteSpeed server banner and do not reveal version numbers.

Finally, NGINX Unit saw a few new releases since the last survey. NGINX Unit 0.4 was released on 15 January. This was the first release of the lightweight web application server to be compatible with DragonFly BSD, but it was mostly a bugfix release that eliminated some significant regressions in the previous version. NGINX Unit 0.5 was then released on 8 February, adding a Perl application module that allows it to run applications like Bugzilla; however, this release was not announced, as it contained a serious regression that could cause the main process to die. This was rectified in NGINX Unit 0.6, which was announced on 9 February.

In the January 2018 survey we received responses from 1,805,260,010 sites across 213,053,157 unique domain names and 7,228,005 web-facing computers. This reflects a gain of 214,000 computers, but only 183,000 domains. Overall hostname growth was 71 million, although the number of active sites fell slightly, by 311,000.

DPS powering GoDaddy's Website Builder

While the total number of domains across all web server vendors grew slightly, 1.5 million fewer domains used a Microsoft web server in the January 2018 survey. Its share of domain names has fallen by 0.74 points to 26.1%. Contributing to that loss were more than 985,000 unique domains hosted by GoDaddy, which are now using a lesser-known web server called DPS.

DPS (Data Protection Server) is now the 10th largest server by domains, and it is used exclusively by GoDaddy to host customer sites that have been created with its Website Builder tool. The DPS server appears to be frequently updated: sites using it currently return the Server: DPS/1.1.20 header, but these sites were using version 1.1.19 when the data was collected for the January 2018 survey. In the December 2017 survey, the sites were using version 1.1.16, and 1.1.10 in November 2017.

Cloud balancing with Pepyaka and F5 BIG-IP

Another lesser-known server, Pepyaka, also saw massive domain growth at a single hosting company this month. The Israeli web development platform Wix uses Pepyaka to host its customers' sites in the Amazon Web Services cloud, but many of these sites did not identify which server software they were using during the previous survey, causing a temporary absence. The number of domains using Pepyaka at AWS is now back up to more than 1.8 million, making it the 6th largest server by domains.

Nearly all of the Wix sites hosted at AWS use Pepyaka 1.11.3, which is likely based on the July 2016 mainline release of nginx 1.11.3; but it looks like Wix is in the process of rolling out an updated version: This month saw the appearance of 22 sites using Pepyaka 1.13.4, which most likely corresponds to the August 2017 mainline release of nginx 1.13.4.

Last month's temporary absence of Pepyaka could have been indicative of wider scale experimentation by Wix. Many of Wix's sites were served from machines that exhibited the TCP/IP characteristic of F5 BIG-IP, whereas this month, those sites are back to using Pepyaka running on Linux.

Wix has been a long-time user of nginx, and originally moved all user traffic to the commercial NGINX Plus product to future-proof its load balancing needs. The temporary appearance of F5 BIG-IP demonstrates that Wix may have been testing the waters with a different load balancing setup.

For most of its life, F5 BIG-IP has only been available on specialist hardware devices, such as BIG-IP appliances or VIPRION chassis; but F5's Virtual Editions make it possible to run BIG-IP software on commodity hardware in the cloud. F5 offers several BIG-IP Virtual Edition Amazon Machine Images (AMIs) in the AWS Marketplace, with pay-as-you-go licensing costs ranging from $0.33 to $4.40 per hour.

In May 2017, F5 also announced new public cloud solutions for Azure and Google Cloud, as well as a private cloud solution for the OpenStack cloud platform. This month's survey found more than 13 million domains being served from F5 BIG-IP devices, with Apache being the most commonly seen Server header.

Apache leads in most metrics, but nginx dominates in growth

Across the entire market, Apache remains in the lead with a 38.2% share of domains, but the ongoing trend makes it likely that both Apache and Microsoft could be overtaken by nginx in the next few years. nginx has continued to steadily increase its domain share, with a 0.21 point gain to 20.5% this month, while Apache has been experiencing a general decline of market share in recent years.

nginx's persistent growth has also manifested itself in every other metric this month, with it gaining the largest number of sites, active sites and web-facing computers, as well as increasing its presence amongst the top million sites. nginx is now used by 23.5% of all web-facing computers and 30.5% of the top million sites, but Apache still has the largest number of active sites, computers, domains and top-million sites.

The only metric graphed below in which Apache does not take the lead is hostnames, where Microsoft has a total of 575 million sites; but this metric is prone to fluctuations and is less indicative of market success. Microsoft has the second largest number of domains in the survey, but has been ranked third in web-facing computers since it was overtaken by nginx in October 2017.

While 1.5 million web-facing computers currently run Microsoft web server software, a slightly larger number – 1.8 million – run Windows operating systems. The bulk of the difference is made up of Windows computers that either run Apache or reverse-proxy traffic from backend Apache servers. The most commonly used Windows version is Windows Server 2008, followed by 2012 and then the aging, unsupported Windows Server 2003. Windows Server 2016 accounts for only 3.7% of all Windows web-facing computers at the moment, but it is steadily growing – this month, the number of Windows Server 2016 computers grew by 14% to 66,800.