IT infrastructure design and integration · System integrator for SMBs

Secure and resilient IT infrastructure for businesses

A modern business IT infrastructure has to do more than simply work. It must keep services running when a component fails, limit the impact of an attack, protect data and allow a recovery you can actually verify. That is why servers, network, security, backup and cloud are designed together, as parts of a single system.

  • Architecture and dependencies
  • Security by design
  • Backup and disaster recovery
  • Proportionate resilience
What an IT infrastructure must deliver
Performance
resources sized for real workloads, not imagined ones
Security
identities, network and systems protected by design
Continuity
critical services stay available when a component fails
Recoverability
data and services can be restored, and you have verified it
Scalability
you grow by adding, not by rebuilding
Manageability
documented, monitored, upgradable
Governance
responsibilities, risks and decisions are clear

Seven properties of the same system: improving one at the expense of the others does not make the infrastructure stronger.

01 The starting point

The IT complexity of a small or mid-sized business has little to do with headcount

A company of twenty people can depend on IT more than one of two hundred. What matters is how much work stops when IT stops.

Today a small or medium-sized business runs on a management system or ERP, a database, Microsoft 365, often an e-commerce site or web applications, shared files, remote access and VPNs, perhaps several offices and cloud services from different vendors. Each of these has its own dependencies, and many are critical to the day's revenue.

That is why the right question is not "how many servers does a company like ours need", but "which services cannot stop, for how long, and with how much data loss". This is how a business IT infrastructure is sized: from the services, not from the org chart.

What really drives complexity

  • Business dependence on IT
  • Criticality of services
  • Users and devices
  • Workloads and applications
  • Number of sites
  • Data volume and growth
  • Tolerance for data loss (RPO)
  • Acceptable recovery time (RTO)
  • Exposure to cyber risk
  • Remote access and third parties
  • Integrations between systems
  • Regulatory and contractual obligations
  • Dependencies on cloud services

02 From separate parts to one system

An IT infrastructure is not a list of products

The most common way to build the IT of a small business is by successive purchases: a server when needed, a firewall after an incident, a backup when someone asks for it. Each piece may be good. The whole rarely is.

Fragmented approach

  • Servers
  • Firewall
  • Backup
  • Antivirus

Bought and managed separately, often from different vendors. No one is accountable for how they behave together when something goes wrong.

System integration approach

  • Business services
  • Applications
  • Identity
  • Endpoints
  • Network
  • Security
  • Compute
  • Virtualization
  • Storage
  • Data
  • Backup
  • Disaster recovery
  • Cloud
  • Monitoring
  • Processes

Designed as a single system: every component is chosen knowing what it depends on, what depends on it and what happens if it stops.

03 What an IT infrastructure is today

IT infrastructure does not mean "servers"

A business IT infrastructure is the set of layers that carry a service from the company's need all the way down to data that is saved and recoverable. Each layer supports the one above it.

  1. Businessthe processes and services the company must deliver
  2. Userspeople, roles, offices, remote work
  3. Identityaccounts, authentication, privileges
  4. EndpointsPCs, laptops, mobile devices
  5. NetworkLAN, Wi-Fi, site-to-site links, VPN
  6. Securityperimeter, segmentation, controls
  7. Compute and virtualizationphysical servers, hypervisors, virtual machines
  8. Storagedisks, NAS, SAN, where the data lives
  9. Applicationsmanagement system, ERP, email, e-commerce, databases
  10. Datathe one thing you cannot buy again if it is lost
  11. Backupseparate, recoverable copies of the data
  12. Disaster recoveryhow systems are brought back into service

Cutting across every layer

  • Monitoring
  • Logs
  • Security
  • Governance
  • Management
Diagram of the layers of a business IT infrastructure. Cross-cutting functions run through every level: a security control or an alert that covers only one layer leaves the others exposed.

04 Why you need a system integrator

Specialization is necessary, but no technology lives alone

The ten misconceptions we meet most often share the same root: a property that belongs to the system is attributed to a single component.

  • High-availability cluster≠recoverable data

    A cluster keeps the service up if a node fails, but it does not protect the data: a deletion, a mistake or ransomware encryption acts on the only copy, or is replicated to the other nodes. Without separate backups, lost data stays lost.

  • Backup≠verified restore

    A backup is only as good as its last successful restore. Until someone has tested it, it is an assumption.

  • Firewall≠protected identities

    The firewall filters traffic, but it cannot tell whether someone logging in with valid credentials is who they claim to be. You need MFA and privilege management.

  • High availability≠disaster recovery

    High availability covers the failure of a component at the same site. Disaster recovery covers the loss of the site, of the data or of the whole environment.

  • RAID≠backup

    RAID tolerates the failure of one or more disks. It does not protect against deletions, logical corruption, ransomware or controller failure.

  • Snapshot≠backup

    A snapshot usually lives on the same storage as the data: if the storage fails or is compromised, you lose both.

  • Replication≠backup

    Replication copies changes, including the wrong ones. It becomes protection only if it keeps restore points over time, separate from production.

  • Cloud≠no responsibility

    The cloud provider manages its own part. Configurations, identities, data and their backups remain largely the customer's responsibility.

  • Cybersecurity≠a product

    Security is a set of controls over identity, network, systems, data and processes. A single product covers only part of it.

  • Compliance≠an installed technology

    Regulatory obligations concern governance, processes and accountability. Technology supports their implementation; it does not replace it.

Often the problem is not a lack of technology. It is a lack of integration: good components that nobody designed to work together.

05 The role of IT consulting

Technology is chosen afterwards, not first

Consulting is the bridge between the needs of the business and the technical architecture. Its job is to define what is needed before deciding what to build it with.

From requirements to evolution

  1. Business requirements
  2. Assessment of the existing environment
  3. Asset inventory
  4. Dependency map
  5. Risk analysis
  6. Capacity and growth
  7. Security requirements
  8. Continuity requirements
  9. RPO and RTO per service
  10. Architecture
  11. Technology selection
  12. Integration
  13. Monitoring
  14. Evolution

When a project starts from the product ("we need a new server", "let's move to the cloud"), the architecture ends up adapting to that choice instead of the other way round. When it starts from requirements, the same decision can turn out right, wrong or simply premature, and you know it before you spend.

In the sequence above, technology selection comes at the eleventh step. Before it come the services to protect, the dependencies between systems, the risks, the expected growth and the downtime the business can sustain. This information tells you whether you need two servers or a cluster, a local backup or an off-site copy as well, a new firewall or a better-segmented network.

This is the work we do in IT consulting and IT infrastructure design: this page explains the overall picture, while the dedicated pages go into the services in detail.

06 The components of the infrastructure

Twelve components, one architecture

For each component: what it does, what it depends on and which risk it manages. This view shows why none of them can be designed on its own.

  • Compute

    Function
    Provides CPU and memory to services.
    Depends on
    Power, cooling, storage, network.
    Risk it manages
    Slowdowns and outages caused by insufficient resources or faulty hardware.
    Business server support
  • Virtualization

    Function
    Separates services into virtual machines and makes them movable.
    Depends on
    Compute, storage (shared or replicated), management network.
    Risk it manages
    A failure or an update that takes several services down together.
    Enterprise server virtualization
  • Network

    Function
    Connects users, offices, servers and external services.
    Depends on
    Devices, cabling, Internet links.
    Risk it manages
    Services that are intact but unreachable; the spread of an attack.
    Business networks and infrastructure
  • Identity

    Function
    Determines who can access what.
    Depends on
    Directory, MFA, onboarding and offboarding processes.
    Risk it manages
    Access with stolen credentials, excessive privileges.
    Two-factor authentication
  • Security

    Function
    Prevents, detects and contains attacks.
    Depends on
    Segmented network, identity, updates, logs.
    Risk it manages
    Compromise and lateral movement between systems.
    Corporate IT security
  • Storage

    Function
    Holds data and virtual machine disks.
    Depends on
    Disks, controllers, storage network.
    Risk it manages
    Loss or slowness of data for every service that uses it.
    Business SAN storage
  • Backup

    Function
    Keeps separate, recoverable copies.
    Depends on
    Separate storage, network, protected credentials.
    Risk it manages
    Permanent data loss after failures, errors or ransomware.
    Business backups
  • Disaster recovery

    Function
    Brings systems back into service after a serious event.
    Depends on
    Off-site backups or replicas, procedures, tests.
    Risk it manages
    Prolonged downtime after the loss of a site or of the environment.
    Backup and disaster recovery
  • Monitoring

    Function
    Makes the state of the system observable.
    Depends on
    Metrics, logs, thresholds, someone who receives the alerts.
    Risk it manages
    Problems discovered by users instead of by technicians.
    Server monitoring
  • Cloud

    Function
    Extends the infrastructure with external services.
    Depends on
    Connectivity, identity, contracts and configurations.
    Risk it manages
    Vendor dependence, ungoverned data and configurations.
    Hybrid cloud for SMEs
  • Applications

    Function
    Deliver everyday work: management system, email, e-commerce.
    Depends on
    Every layer below.
    Risk it manages
    This is where users see the outage, whatever the cause.
  • Governance

    Function
    Assigns responsibilities, priorities and decisions.
    Depends on
    Documentation, inventory, processes.
    Risk it manages
    Improvised interventions, unseen risks, nobody deciding.

07 The dependency chain

A business service is a chain: it breaks at the weakest link

The user sees "the management system is down". Underneath there are at least ten levels, and the failure of just one is enough to stop the service even if all the others work.

  1. Business serviceissuing an order, invoicing
  2. Applicationthe management system
  3. Databasewhere the application writes
  4. Virtual machinethe system hosting the database
  5. Hypervisorthe server running the VMs
  6. Storagethe VM disks
  7. Networkswitches, VLANs, internal firewall
  8. Identity and securitywho can access, and from where
  9. Backup and DRhow you go back
  10. Monitoringwho notices, and when

Example scenario

The server is on, but the business is at a standstill

The shared storage reaches its space limit. The hypervisor is running, the virtual machines show as on, the network responds. But the database can no longer write, the management system throws errors and orders stop.

No component is "broken" in the classic sense. The problem is that nobody had linked data growth to storage capacity and to an alert that would fire before the blockage. It is an integration error, not a technology one.

Thinking like a system integrator means starting from the service and walking down the chain, asking for each link what can stop it, who notices and how it is restored.

08 Reference architecture

A conceptual example of a resilient architecture

It is not a model to copy: it is a diagram to show how the components connect. Every company builds a version proportionate to its own services and risks.

Conceptual example of a resilient IT architectureFrom the top: the Internet, perimeter security, network segmentation, a three-node virtualization cluster, storage, virtual machines, a backup system that splits into a local copy and an off-site copy, the latter with an isolated or immutable copy, and a disaster recovery environment. The on-site components sit in one frame; the off-site copy, the isolated copy and DR sit in a second frame linked by a replication arrow. On the right, a vertical band with identity, monitoring, logs, security and management, which apply to every layer.ACROSS EVERY LAYERIdentityMonitoringLogsSecurityManagementInternetMAIN SITEPerimeter securityNetwork segmentationVirtualization clusterServices and VMsNodeNodeNodeStorageBackup systemLocal copyOFF-SITE OR CLOUDreplicationOff-site copyIsolated / immutableDR environmentrestoreConceptual example of a resilient IT architectureFrom the top: the Internet, perimeter security, network segmentation, a three-node virtualization cluster, storage, virtual machines, a backup system that splits into a local copy and an off-site copy, the latter with an isolated or immutable copy, and a disaster recovery environment. The on-site components sit in one frame; the off-site copy, the isolated copy and DR sit in a second frame linked by a replication arrow. On the right, a vertical band with identity, monitoring, logs, security and management, which apply to every layer.InternetMAIN SITEPerimeter securityNetwork segmentationVirtualization clusterServices and VMsNodeNodeNodeStorageBackup systemLocal copyOFF-SITE OR CLOUDreplicationOff-site copyIsolated / immutableDR environmentrestoreACROSS EVERY LAYERIdentityMonitoringLogsSecurityManagement
Conceptual example of a resilient architecture: perimeter, segmentation, virtualization cluster, storage, local and off-site backup with an isolated copy, disaster recovery environment. Identity, monitoring, logs, security and management run through every level.
  • Perimeter and segmentation

    The firewall separates the company from the Internet, but it is internal segmentation that stops the compromise of one PC from reaching servers and backups.

  • Cluster and storage

    Multiple nodes make it possible to move virtual machines during failures and maintenance. If the storage is shared (SAN or NAS) and is not itself redundant, it remains a single point of failure under all the nodes; with distributed or replicated storage, such as Ceph, the data sits on several nodes but you need a dedicated network and correct sizing. In no case does it replace backup.

  • Multi-tier backup

    The local copy serves quick restores, the off-site copy covers the loss of the premises, and the isolated or immutable copy covers cases where an attacker also reaches the backups.

  • Disaster recovery

    The DR environment can be a second site, a cloud infrastructure or a rebuild procedure: what matters is that it is documented, sized and tested.

09 Virtualization and Proxmox

Virtualization organizes workloads; it does not protect them on its own

It is the layer that makes a modern infrastructure manageable. For this very reason it must be designed together with storage, network and backup.

Virtualizing means running several logical servers on the same hardware, each isolated from the others. The benefit is not only consolidation: it is being able to treat a server as an object that you create, move, clone and restore.

  • Consolidation. Less physical hardware for the same number of services, with resources assigned according to real load.
  • Isolation. Each role in its own virtual machine: the peak or failure of one service does not drag down the others.
  • Provisioning. A new server is prepared in minutes from a template, not in days.
  • Clusters and high availability. With multiple nodes and shared or replicated storage, VMs are automatically restarted on another node if one fails.
  • Maintenance. With shared or replicated storage you update one node at a time by migrating VMs, normally without stopping services.
  • Migration and growth. You add capacity or change hardware without reinstalling services.

Where we use Proxmox VE

Proxmox VE is an open source virtualization platform that we use in client projects when it fits the requirements, and on our own infrastructure: Hector Cluster, the infrastructure that runs TN Solutions' Hector services (Hector AI, Hector LIS, Hector Biz), is built on Linux environments virtualized with Proxmox behind a pfSense perimeter.

It is not always the right choice. Where VMware licenses are already in place, in-house skills are well established or applications have specific certification requirements, the evaluation may point elsewhere. The comparison should be made on cost, features, skills and migration path, not on the label.

High availabilitythe service restarts if a component fails
Backupdata can be recovered to a point in time
Disaster recoverythe whole environment returns to service after a serious event

10 Open source in business

Open source or proprietary: decide on the architecture, not on the label

Mature open source technologies have a concrete role in business infrastructures. Not because they are always better or always cheaper, but because in many cases they offer a good balance of control, interoperability and total cost.

  • Interoperability

    Open standards and documented formats make integration with the rest of the infrastructure easier.

  • Control

    Configuration and behavior can be inspected: you know what you are running.

  • Licensing

    No usage license fee, but professional support is often subscription-based (for Proxmox VE, per CPU socket).

  • Vendor lock-in

    Less dependence on the commercial choices of a single vendor, as long as data and procedures also remain portable.

  • Supportability

    You need someone who can run it in production: in-house staff, a vendor or the community are not equivalent.

  • Skills

    License savings turn into cost if the skills to configure and maintain it are missing.

  • Lifecycle

    Versions, updates and end of support must be planned like for any product.

  • TCO

    Total cost includes licenses, hardware, skills, maintenance, downtime and the exit from the platform.

Open source technologies we use and document

  • Proxmox VEvirtualization and clustering
  • Linuxservers and application services
  • pfSensefirewall and segmentation
  • HAProxyload balancing and TLS termination
  • MariaDB and Galeradatabase and synchronous replication
  • Redisin-memory cache and sessions
  • Elasticsearchsearch engine
  • Dockercontainerized application services

Technology should be chosen according to architecture, requirements and TCO, not the open source or proprietary label. In the same infrastructures we also use Windows Server, VMware, WatchGuard and Synology, when they are the best answer.

11 Applications and Microsoft 365

Applications are the last link, and they often live in the cloud

Email, documents, collaboration and identity increasingly run on Microsoft 365. That doesn't take them out of the infrastructure: it makes them part of it, with the same questions about security, recoverability and governance.

A Microsoft 365 tenant depends on user identities, on the devices people sign in from, on the network and on the domain's DNS records. In turn it carries the company's email, files and communication. It is a component of the architecture like any other, and it should be designed with the same criteria.

The typical mistakes are the ones described above: a tenant with no MFA on admin accounts, an email migration that forgets DNS and shared mailboxes, a file server copied into SharePoint with all its clutter, licenses chosen without knowing which controls are needed, data left to the recycle bin as if it were a backup.

  • Exchange Online email and calendars: identity, DNS, security and migration are designed together.
  • SharePoint, OneDrive and Teams content and collaboration: information architecture and permissions first, migration second.
  • Entra ID and Intune identity, Conditional Access and devices: the new perimeter.
  • Licensing the right plan depends on roles, devices and required security controls, not on price.
  • Backup retention and the recycle bin are not an independent backup of tenant data.

12 Cybersecurity by design

Security and infrastructure are not designed separately

A flat network, a backup reachable with domain credentials or an exposed management panel cannot be fixed with one more product: they are architectural choices.

  • Segmentation

    Separate networks for users, servers, management, guests and backup, with explicit rules between zones.

  • Firewall and VPN

    Controlled perimeter and remote access only through encrypted, authenticated channels.

  • MFA

    Multi-factor authentication at least for remote access, email and administrative accounts.

  • Least privilege

    Each account has only the permissions it needs, and elevated privileges are kept separate from everyday use.

  • Hardening

    Unneeded services switched off, secure configurations, management interfaces not reachable from untrusted networks.

  • Patch management

    Planned updates for systems, firmware and applications, prioritizing actively exploited vulnerabilities.

  • EDR

    Detection and response on endpoints and servers, where the risk justifies it.

  • Logging and monitoring

    Events collected and retained to understand what happened and to notice it in time.

  • Vulnerability management

    Periodic checks, from vulnerability assessment to penetration testing when needed.

  • Administrative access

    Dedicated workstations and paths for management, backup credentials distinct from domain credentials.

Every control depends on the others: MFA protects identities, segmentation limits the damage if an identity is compromised anyway, logs make it possible to reconstruct what happened and isolated backups make it possible to restart.

13 NIS2 as an example

Why NIS2 talks about continuity and backup, not just security

The NIS2 Directive is a good example of how risk, security and continuity are now treated together.

Directive (EU) 2022/2555, transposed in Italy by Legislative Decree No. 138 of 4 September 2024, requires essential and important entities within its scope to adopt proportionate risk-management measures that go beyond technical protection (Article 21): they include business continuity, with backup management, disaster recovery and crisis management, incident handling, supply chain security and assessment of the effectiveness of the measures. Management bodies approve the measures and are accountable for them (Article 20).

Not all small and medium-sized businesses fall within the scope of NIS2: applicability depends on sector, size and other criteria set by the law, and must be checked case by case. But the list of measures is useful to anyone, because it describes the areas a resilient infrastructure must cover.

No technology makes a company compliant on its own. A well-designed infrastructure supports the implementation of the measures; compliance remains the responsibility of the organization, which builds it with processes, documentation and governance. We support our clients on the technical side.

Areas that NIS2 brings together

  • Risk analysis and security policies
  • Incident handling
  • Business continuity, backup and disaster recovery
  • Supply chain security
  • Vulnerability management
  • Access control and asset management
  • Assessment of the effectiveness of measures
  • Cryptography and multi-factor authentication
  • Cyber hygiene, training and accountability of management bodies

Primary sources

Technical content for information purposes, not legal advice. To establish whether and how NIS2 applies to your organization, refer to the official sources and to a legal advisor.

14 Backup, disaster recovery and continuity

From saved data to restored service

Backup, disaster recovery and business continuity are three different levels of the same question: what happens, and how quickly do you restart, if something is lost.

  1. Productionthe data and services in use
  2. Backupcopies at defined intervals
  3. Separationon systems and credentials different from production
  4. Off-sitea copy far from the main site
  5. Isolation or immutabilitya copy that an attacker, even with compromised credentials, cannot delete or modify for the duration of the retention period
  6. Restore testingproof that the copies work
  7. Disaster recoverythe procedure to bring systems back into service
  8. Business continuityhow the company keeps working in the meantime
RPO · Recovery Point Objective
The maximum amount of data the company accepts to lose, expressed as time. With a single nightly backup, the RPO you can actually achieve is up to 24 hours: you go back to the previous night's data.
RTO · Recovery Time Objective
The maximum time within which a service must be available again after an interruption. It depends on where the copies are, how large they are and how ready the procedure is.
Backup
A copy of the data, separate from production, from which a previous state can be restored.
Disaster recovery
The set of infrastructure and procedures to bring systems back into service after an event that makes the main environment unusable.
Business continuity
The organization's ability to continue essential activities during and after a disruption, including IT but not only IT.
What each technology or process protects, and what it does not
Technology or processWhat it protectsWhat it does not protectRole in the architecture
RAIDThe failure of one or more disks, depending on the levelDeletions, corruption, ransomware, controller or server failureStorage availability
SnapshotA quick return to a previous state, for example before an updateFailure or compromise of the storage it resides onOperational tool, not an independent copy
ReplicationAvailability of an up-to-date copy on another systemErrors, deletions and encryption, which are replicated; it protects against these only if it keeps restore points separate from productionLower RTO and a basis for high availability or DR
BackupRecovery of data to a point in timeService downtime during the restore; data loss after the last copyData recoverability
Off-site backupLoss of the premises: fire, theft, floodingAn attack that also reaches the remote copy with the same credentialsGeographic protection
Immutable or isolated backupDeletion or encryption of backups by an attackerData produced after the last copy; a backup already compromised at the source (encrypted data or dormant malware copied); a restore that was never testedLast barrier against backup deletion
High availabilityThe failure of a component: node, power supply, linkLogical errors, ransomware, loss of the siteService continuity, normally at the same site (stretched multi-site clusters are a separate case)
Disaster recoveryLoss of the main environmentA plan that was never tested; data after the last copy or replica (RPO); downtime during the restoreRestoring services within the defined RTO
Business continuityContinuity of the company's essential activitiesIt does not replace any of the technical levelsOrganizational framework that coordinates them

A backup strategy has operational value only when restore is verifiable: that is why restore tests are a step of the architecture, not an optional activity.

15 Three levels of criticality

There is no single right infrastructure for every business

The scenarios below show how choices change as criticality grows. They do not depend on company size: a small business can sit at the third level, a large one at the first.

  • Standard services

    A few hours of downtime is an inconvenience, not serious damage. Data changes little over the course of the day.

  • Business-critical services

    The management system, production or sales stop when IT stops. Every hour of downtime and every piece of lost data has a measurable cost.

  • High criticality or specific requirements

    Services that cannot stop, regulated data, strict contractual or regulatory obligations.

How architectural choices change as service criticality grows
AspectStandard servicesBusiness-critical servicesHigh criticality or specific requirements
RedundancyCritical components made redundant (disks, power)Redundant servers and network on critical servicesExtended redundancy, including across sites
High availabilityUsually not necessaryClusters on critical servicesClusters and services designed for failover
BackupLocal and off-siteMore frequent, with an isolated or immutable copyMultiple tiers, defined retention, isolated copies
RPO / RTODefined, even if broadDefined per service and verifiedTight, contractual and tested
MonitoringStatus of systems and backupsMetrics, thresholds and alerts with escalationContinuous monitoring with on-call coverage
Security controlsFirewall, MFA, updates, antivirus or EDRSegmentation, EDR, centralized logsExtended controls, periodic checks and testing
Disaster recoveryDocumented rebuild procedureDR plan with a recovery environmentDR site or environment ready and tested
TestingSpot-check restoresScheduled restore testsPeriodic DR exercises
DocumentationInventory and network diagramPlus operating and recovery proceduresPlus roles, responsibilities and a test log
SLAStandard response timesGuaranteed times on critical servicesTight SLAs and extended coverage

Indicative values to show the logic, not universal requirements: RPO, RTO and SLA are defined service by service during the assessment.

16 What happens without integration

Nine problems that arise between one component and the next

None of these cases requires the wrong technology. The right technology put together without a plan is enough.

  • Virtualization without capacity planning

    VMs are added one at a time until storage or memory saturate and slow down every service at once.

  • Backup without restore testing

    On the day it is needed, you find the copies are incomplete, unreadable or take days to come back online.

  • Cybersecurity without an inventory

    You cannot protect what you do not know you have: the forgotten server is the one without updates.

  • Firewall without segmentation

    The perimeter holds, but once inside, an attacker reaches servers and backups from the user network.

  • Cloud without governance

    Services activated by different departments, accounts without MFA, data outside any company backup.

  • High availability without disaster recovery

    The cluster survives the failure of a node, but ransomware or a fire hits all the nodes together.

  • Monitoring without escalation

    The alert fires, lands in a mailbox nobody reads, and a customer reports the problem.

  • Fast application on slow storage

    The new management system is high-performing on paper, but the database and storage are still those of five years ago.

  • Unprotected privileged accounts

    A single administrator credential, without MFA, also used for email: it is the key to everything.

Often the problem is not the absence of technology. It is the absence of integration.

17 The role of the system integrator

What a system integrator actually does

The value does not lie in knowing how to install one more product, but in designing and governing the way all the products work together.

  1. Understands the business service before the technology
  2. Identifies dependencies between systems, applications and vendors
  3. Spots single points of failure
  4. Assesses risk and turns it into priorities
  5. Defines security and continuity requirements, RPO and RTO
  6. Designs the architecture
  7. Selects technologies suited to the requirements
  8. Integrates the components and verifies how the whole works
  9. Considers security, recoverability, capacity and performance in the same project
  10. Defines monitoring and escalation
  11. Plans the lifecycle: updates, renewals, decommissioning

What it does not mean. A system integrator does not have to build every technology in-house. It can coordinate vendors, cloud services and specialists: what it cannot delegate is responsibility for how the whole behaves.

18 · A real case

Initpc: an e-commerce site that is an infrastructure

For Initpc, whose technical partner we have been since 2006, we run an e-commerce site with over 280,000 products in the catalog and more than one million images.

We do not mention it to tell a client story, but because it shows the thesis of this page well: a single business service, selling online, requires expertise in virtualization, Linux, networking, security, databases, caching, search, storage, backup, monitoring and software, designed to work together.

The design criterion documented in the case study is clear: for each layer we asked what happens if it stops. Only the HAProxy entry point and the MariaDB database really shut the shop down, and monitoring and recovery procedures concentrate on those; the other layers are designed to degrade rather than block sales.

All technical information comes from the published case study. We do not report uptime, RPO or RTO figures that the case study does not state.

The skills a single service required

  • VirtualizationProxmox VE on Ubuntu Server, one VM per role
  • Entry pointHAProxy for load balancing and TLS termination
  • CacheVarnish for pages, Redis for objects and sessions
  • DataMariaDB on a dedicated VM, with its own backups
  • SearchElasticsearch in Docker
  • PerimeterpfSense and network segmentation
  • MonitoringHector LIS for intrusions and traffic
  • Storage and backupmedia on separate storage, VM images, database dumps
  • Softwareintegration with the management system and warehouse synchronization
  • AIHector AI for product pages

19 The method

From analysis to continuous improvement

These are the phases we follow in infrastructure projects, from consulting to management: consistent with the approach of IT systems design, from requirements analysis to testing and go-live, with backups, access controls, updates and active monitoring.

  1. Analysis

    Business requirements, inventory, dependencies, risks and current situation, service by service.

  2. Design

    Architecture, RPO and RTO per service, security, capacity and technology selection.

  3. Integration

    Phased implementation, migration of services and testing of the whole, not of the individual pieces.

  4. Protection

    Security controls, multi-tier backups and disaster recovery procedures.

  5. Monitoring

    Metrics, alerts and escalation to whoever intervenes.

  6. Verification

    Restore tests and periodic checks: what is not tested is not considered working.

  7. Improvement

    Updates, risk review and evolution of the architecture with the business.

20 What a resilient infrastructure costs

The factors that determine the cost

There is no per-user or per-server price that makes sense in the abstract. There are factors that, combined, determine the investment and the running cost.

  • Size

    • Users and devices
    • Sites to connect
    • Servers, VMs and workloads
    • Data volume and growth
  • Continuity

    • Criticality of services
    • Required RPO and RTO
    • High availability
    • Backup retention
    • Off-site copy and disaster recovery
  • Security and rules

    • Security requirements
    • Regulatory and contractual obligations
    • Periodic checks and testing
  • Management

    • Monitoring
    • SLAs and response times
    • On-call coverage
    • Lifecycle and renewals

Why two similar small businesses can spend very differently. Two companies with thirty employees: the first mostly uses cloud services and can tolerate half a day of downtime; the second produces on an in-house management system, has two offices and loses revenue every hour of outage. Same headcount, different requirements for RPO, RTO, redundancy and monitoring: different infrastructures, and different costs.

21 Checklist

Twenty questions to assess your IT infrastructure

A practical check, without scores: every "no" or "I don't know" answer is a point to look into.

  • Knowledge

    • Is there an up-to-date inventory of assets and services?
    • Is there an up-to-date network diagram?
    • Are the dependencies between critical services documented?
    • Is it clear who is responsible for what, including among vendors?
  • Security

    • Is the network segmented?
    • Do updates follow a planned process?
    • Do administrators use MFA?
    • Are privileges assigned on a need basis and reviewed?
    • Are logs collected and retained?
  • Recoverability

    • Are backups stored on systems separate from production?
    • Is there an off-site copy?
    • Is there an isolated or immutable copy where needed?
    • Are restores tested periodically?
    • Are RPO and RTO defined for every critical service?
  • Continuity and management

    • Is there high availability where it is needed, and only there?
    • Is there a written disaster recovery plan?
    • Do alerts have an escalation path?
    • Is the operational documentation up to date?
    • Are there periodic tests of the whole?
    • Is the lifecycle of hardware and software planned?

The checklist does not replace an assessment: it helps you understand where to start.

Not isolated services: parts of the same architecture

IT consulting
understands business, requirements, risks and constraints
Architecture
defines how the components must work together
System integration
integrates technologies and systems
Cybersecurity
protects identity, network, systems and data
Virtualization
organizes workloads and makes them manageable
Networking
connects and segments
Storage
supports data and workloads
Backup
protects the recoverability of data
Disaster recovery
plans the restoration of services
Business continuity
protects the continuity of work
Monitoring
makes the system observable
Cloud
extends the architecture when appropriate
Open source
offers technologies to use when consistent with requirements and TCO
NIS2
shows why risk, security, continuity and governance must be addressed together

Technologies are tools. Architecture is the value. Consulting establishes what is needed, system integration makes the parts work together, and IT resilience lets the system support the business even when something goes wrong.

22 · Infrastructure assessment

Request an IT infrastructure assessment

We start from your services and from how you work today. The result is a clear picture of risks, priorities and proportionate actions, not a quote for products.

What it may include

  • Current architecture
  • Dependencies between services
  • Single points of failure
  • Virtualization
  • Network
  • Cybersecurity
  • Backup and recoverability
  • Monitoring
  • Capacity
  • RPO and RTO
  • Scalability
  • Lifecycle

The scope of the assessment is agreed at the start, based on the size and criticality of the environment.

We use cookies

We use technical cookies required for the site to work and, only with your consent, analytics and marketing cookies. You can accept, refuse or choose category by category. If you continue browsing to another page without choosing, cookies are considered accepted. Cookie Policy