IT infrastructure security

IT infrastructure and business systems security

Practical security for Linux and Windows servers, limiting public services, firewall, VPN, multi-factor authentication, safe updates and backup checks based on the real risks to your operations. I carry out remote reviews and changes across the Czech Republic.

Protective layersProtective layersDefense in depth
Attack surface
Security hardening of Linux and Windows servers
Accounts, administrator access and permissions
Firewall, VPN and network segmentation
01
Security hardening and updates

Removing unnecessary services, a more secure operating system and application configuration, and a plan for installing security patches.

02
Access, MFA and VPN

Reviewing users and permissions, restricting administration to secure channels and multi-factor authentication wherever it is supported.

03
Detection and recovery

Logging, monitoring of suspicious events, separate backups and a procedure for safely restoring operations after an incident.

Protected state
MFA and restricted administrationRestricted
Logging, monitoring and alertsMonitored
Backups and recovery after an incidentRecoverable
The goal is for an attack to cross as little surface as possible: the attack surface is reduced first, only then the costlier controls come into play.

First, reduce the attack surface.

I start with an inventory of public services, accounts, administrator keys, updates and backups. I rank the findings by impact and introduce changes in a way that does not cause a new outage.

When not to put security off

A review is appropriate before publishing a new service, after a change of administrator, as the number of users grows or after an incident. It also makes sense when the business does not know all of its public entry points.

  1. Several people share administrator accounts
  2. Public-facing services have not been updated for a long time
  3. Former employees may still have valid access
  4. Backups can be reached from the same environment as production

How can a small business improve its cyber security in practice?

In practice

Most risks can be reduced with basic, inexpensive steps – before a business considers more costly work or a new security product. Practical business security therefore starts by closing off the most likely attack paths, not by buying a single product. First, publicly accessible services, administrator accounts, remote access, updates, network dependencies and the ability to recover are mapped. This is followed by introducing multi-factor authentication, the principle of least privilege, a secure VPN, separation of sensitive devices, regular patching and central monitoring of important events. Backups must be separated from everyday accounts and restorable in practice. Measures are ordered by impact and effort, so that risks with a high likelihood or serious consequences are removed first. The result is a concrete plan, traceable changes and less reliance on someone noticing a problem by chance.

What to consider when deciding

Security hardening is appropriate after a quick audit, when taking over infrastructure, before publishing a new service or after an incident. The scope must match the actual systems and the owner’s authorisation; a penetration test always has a target and rules defined in writing beforehand. Security hardening means specific configuration changes. An audit finds weaknesses and ranks them by priority. A penetration test actively verifies whether they can be exploited, and incident response begins once there is already a suspicion of compromise; these four activities therefore cannot be lumped together under one vague request for “security”. A business should ask for a list of findings with priorities, an explanation of their impact and verification of the fix, not just an automated report. Ongoing security then continues with monitoring, updates, access reviews and restore tests.

What a security review covers

The depth of the review depends on the scope and criticality of the system. Every change must have its own safe procedure and a way back.

  • Security hardening of Linux and Windows servers
  • Accounts, administrator access and permissions
  • Firewall, VPN and network segmentation
  • MFA and restricted administration
  • Logging, monitoring and alerts
  • Backups and recovery after an incident

IT infrastructure security - what to prepare for the initial diagnosis

  1. To start, identify your most important data and services, public addresses and domains, the remote access methods in use and the people with administrator rights.
  2. Prepare information on updates, multi-factor authentication, antivirus protection, logging and the last restore test.
  3. If the work includes active testing, the owner of the systems must confirm in writing beforehand the permitted scope, timing and a contact person in case of an unexpected impact.
  4. A list of requirements from customers or your insurer, and any related internal rules that the proposed measures must meet, is also useful.

The exact scope and price can only be set based on the environment, the available information and the impact of a potential outage. The full process from first contact to handover is described on the How I work page.

Specific risks and changes, ranked by priority.

The output is an overview of the weaknesses found, the changes made and further recommendations for the specific system. I connect security with monitoring and recovery, because prevention alone is not enough.

  • A list of publicly accessible services and entry points
  • Reviewed accounts, keys and administrator permissions
  • Security in place: firewall, VPN and available MFA
  • Documented changes, open risks and a recovery procedure

Indicative prices from the price list

Security audit and system hardening
from CZK 8,000
Penetration test of 2–4 person-days
from CZK 25,000
Full price list

Frequently asked questions - Cyber security

What does securing IT systems involve?

Securing IT systems includes limiting public services, updates, reviewing accounts and permissions, MFA, firewall, VPN, network segmentation, logging, monitoring and restorable backups. Measures are prioritised according to the real risk and the impact on operations.

What does an IT infrastructure security review include?

The scope can include publicly accessible services, updates, accounts and permissions, administrator access, the firewall, VPN, available MFA, logging, monitoring and whether backups are ready to be restored.

Can security be improved without downtime?

Some checks can be carried out without affecting operations. I plan changes that affect availability one by one, verifying dependencies and keeping a way back; any maintenance window is agreed in advance.

Is recovery after an incident also part of security?

Yes. Prevention alone is not enough, so I also check that backups are separated, available and covered by a documented recovery procedure. The specific restore test depends on the scope of the system and the agreed service.

Does the new Czech Cyber Security Act (NIS2) apply to my business?

Since November 2025, Act No. 264/2025 Coll. has been in force; depending on the sector and the size of the business, it may bring specific security obligations even where no regulation applied before. Whether and under which regime the act applies to your business needs to be assessed individually. If it does, I can help design and implement appropriate security measures that build on the actual state of your infrastructure.

Do you also offer penetration testing?

Yes, as a separate service with a target, scope and rules defined in writing beforehand. Unlike security hardening or an audit, a penetration test actively verifies whether a specific system can be exploited; it often follows an audit or is ordered on its own for a precisely defined target.

Not sure where to start? Describe the situation.

A few sentences about what is not working or what you need are enough. I will reply with a suggested first step and an estimate of the scope.

Let’s talk

Prices of the core services are listed in the indicative pricing.