Glossary Entry
What is Firewall?
What Firewall actually means, buzzwords removed — with the example that makes it land.
The short answer
Rules you write are what a firewall filters network traffic against, deciding which connections may reach which services and turning everything else away by default.
What follows: the longer explanation, a picture that holds, the practical stakes, and the places you will genuinely meet it.
By the Hosting & Domains team · Reviewed 18 August 2026
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Terms in the jargon buster
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English throughout
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People, if you get stuck
On a server the sensible shape is deny all inbound, then permit what you genuinely need, usually SSH and the web ports. Whatever remains is genuinely unreachable rather than merely undocumented. That gets enforced on the machine by host firewalls like ufw or firewalld, and further upstream by network-level filtering.
It complements application security rather than replacing it. The firewall governs what can be reached at all, while what happens on the ports you did open belongs to the WAF and to keeping your applications in order.
The everyday parallel
A gatehouse with a list of expected visitors on the desk. Named callers are directed to the right department, and everybody else meets a closed barrier instead of wandering into an unlocked lobby.
Carry that picture with you and most documentation on the topic loses its mystery on a first read.
Why this term earns a page
Leave a server without a firewall and every running service is on offer to the internet's endless scanning traffic. Putting a default-deny policy in place takes about five commands and ranks among the highest-value time anybody spends on a machine.
That, incidentally, is the bar for any technical term — not 'could I lecture on it' but 'would I recognise it as the answer to my problem'. For this one, you now would.
One worked example
A VPS keeps its database private. The web ports face the world while the database port is open to localhost alone, so the scanners hammering it from every continent get no answer whatever.
Scale that example across every website online and you have described the whole job of the concept in one stroke.
Where it sits inside your own account
Here it largely looks after itself, since the defaults are sensible and the panel puts the controls within reach the moment you want them. Read on: WAF, DDoS Attack, VPS and SSH.
A free SSL certificate comes with every plan and reissues itself before the old one lapses — the padlock is never yours to diarise.
A jargon buster from the people who answer the tickets
An unexplained piece of jargon is, to us, a service defect. This is the support team's collected translations, published where a search engine can hand them over on our behalf.
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- 100+ entries, plain English all the way
- Ordinary analogies, working examples
- Neighbouring ideas linked together
- Written by our own support engineers
Why Hosting & Domains
Standard on every plan
This term, properly landed
Firewall defined, pictured by analogy and located in your own panel — recognise-level after a single read.
Jargon-free by design
Definitions written for people who run sites, not for other sysadmins — translation rather than restatement.
Cross-wired entries
Related terms point at each other, so one lookup compounds into working knowledge.
The next step, drawn out
Carry on into WAF and DDoS Attack — ideas rarely travel alone, so the neighbours are linked in.
Clear about how deep to go
Most of these are recognise-level rather than operate-level, and every entry says which it is.
Analogies that hold
Every concept comes with a mental model that returns exactly when you need it.
Quick Start
Order placed to site online
- 1
Find it in your own account
Nothing teaches a hosting term faster than finding it in your own panel; five minutes of looking beats an hour of reading.
- 2
Check the defaults as they stand
The platform ships sensible defaults for this — check rather than assume, and your setup becomes something you know instead of hope.
- 3
Chase the neighbouring terms
Hosting terms travel in groups — WAF, DDoS Attack and VPS finish this one's picture, each a two-minute read away.
Built In
Fitted to every plan
- Staging copies for trying a change before it goes live
- Mailboxes that answer at the name you hold
- 99.9% uptime as the target, watched around the clock
- The name's first year included when you order annually
- WordPress Toolkit, with the updates seen to for you
- Spam and virus screening on every mailbox by default
- SSH, Git and Composer on the developer plans
- WordPress and 400+ further applications installed in one click
- Free SSL on every plan, reissued before the old one lapses
- LiteSpeed caching in the server itself rather than bolted on by plugin
Frequently Asked
The questions that come up most
Do shared hosting customers configure a firewall?
No. Running the platform's firewalls and protections falls to us, and that responsibility is most of what the word managed means. Firewall administration becomes yours at the VPS tier, where the machine belongs to you and so does the list of who gets in.
What is the difference between a firewall and a WAF?
They work at different heights. Ports and addresses are the firewall's business: may this connection reach this service, yes or no. The WAF takes over afterwards, reading the HTTP content of whatever got through and judging whether the request is an attack. A serious setup runs both.
What happens when I outgrow the plan?
You upgrade in place. Plan changes are made from the client area with no migration and no downtime, and the range runs from small shared accounts through VPS to full dedicated machines. Growth becomes a setting on the account rather than a search for a new host.
Does hosting include mail?
Yes — every hosting plan includes mailboxes at your own name, with webmail, IMAP, POP and SMTP plus spam filtering on from the start. There is standalone email hosting too, for a name whose website lives somewhere else.
Keep reading
DDoS Attack
A DDoS attack floods a target with traffic from thousands of sources at once, aiming to exhaust its capacit…
VPS (Virtual Private Server)
A VPS is a portion of a physical server run as a machine in its own right, with reserved CPU and memory and…
How to Set Up a Firewall with UFW
A walkthrough to follow with the panel open in the next tab.
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