Assets with unknown warranty, support and renewal dates slow decisions when problems arise. This article explains how to build and maintain an IT inventory of hardware, software, accounts and services.
Is the failed server still under warranty, where is the laptop of the employee who just left, when does the domain name need renewing? In many businesses these questions are only asked when something goes wrong, and the answers are scattered across a few people's memories or a pile of invoices. An IT asset inventory is the record that keeps a business's technology assets in one place, up to date and in usable form.
What is an inventory actually for?
An inventory is not just the answer to "what do we have?"; it is a tool that speeds up everyday decisions. A few typical situations:
- Hardware failure: With the serial number and warranty end date to hand, a service request can be opened in minutes, and it is easier to decide between repair and replacement for a device out of warranty.
- Security advisory: When a vulnerability is announced in a particular model or software version, the question "do we have this, how many, and where?" can be answered with a single search.
- Employee departure: If the devices, accessories and accounts issued to an employee are listed, everything can be recovered.
- Budget: With purchase dates and end-of-support dates visible, devices due for replacement next year can be planned ahead, avoiding sudden spending when several devices age out at once.
- Licences and data: Knowing which software is installed where, and which devices hold sensitive data, supports licence compliance and the protection of personal data.
What should the inventory include?
Hardware
Computers, servers, phones and tablets, network devices (firewall, modem, switches, wireless access points), printers, IP cameras, network storage devices and uninterruptible power supplies make up the core list. External drives and USB sticks used for backup should be recorded too, as they carry data. Tracking low-value accessories such as mice or cables individually may not be necessary; set a value threshold for these, but record every device that holds data regardless of the threshold.
Software and licences
Installed software, subscriptions and licence entitlements are kept in a separate section. The aim here is not to write down every program on every computer by hand, but to know the products the business uses, licence quantities, renewal dates and where licence documents are kept. The installed-software list should, where possible, be pulled automatically from a management tool.
Accounts and services
The most commonly forgotten part of an inventory is the non-physical assets: domain names and DNS service, email and cloud services, internet lines (with subscriber and circuit numbers), website hosting, SSL/TLS certificates, and manufacturer and supplier portals. For each, record which company the account is registered to, who holds administrator access, and the billing and renewal dates. Business accounts opened with a personal email address often come to light during this exercise and should be moved to a company address.
Dates
Warranty end, manufacturer end of support, subscription renewal, and domain name and certificate expiry dates are the most valuable fields in the inventory. A missed domain or certificate renewal can bring the website and email to an unexpected stop.
Example field list
Rather than trying to fill in every field from the start, begin with a small number of fields you can keep up to date. An example structure for hardware:
| Field | Example | What it is for |
|---|---|---|
| Asset number | IT-0142 | Matches the record to the label on the device |
| Type and model | Laptop, model name | Used for security advisories and replacement planning |
| Serial number | Number on the manufacturer's label | Needed for warranty and service requests |
| User / owner | Employee name or department | Tracking issue and return |
| Location | Head office, 2nd floor | Makes devices easier to find during counts and faults |
| Purchase date and supplier | Invoice date and number | Warranty claims and replacement planning |
| Warranty / support end | Day, month, year | Repair and budget decisions |
| Operating system or firmware version | Version number | Update tracking and support status |
| Network details | Static IP address, network segment | Troubleshooting and network planning |
| Data and encryption | Holds sensitive data / disk encrypted | Risk assessment for loss, theft and disposal |
| Status | In use, in storage, under repair, disposed of | Separates devices actually in use |
How to get started
For a small business, a well-organised spreadsheet may be enough to begin with; as the number of devices grows, inventory or device management tools make the job easier. Compile the first list from several sources: purchase invoices, a scanning tool that lists devices connected to the network, management software installed on computers, the admin consoles of cloud services and the user directory. Then walk through the offices, carry out a physical count and stick an asset number label on each device.
Automated tools reliably collect hardware models, installed software and versions; but they cannot know who a device was issued to, its warranty date or what work it is used for. The best results come from combining automatically collected data with business information kept by hand.
Trying to record everything at once is one of the common reasons inventory projects stall. Start with the assets whose failure would stop the business: servers, network devices, internet lines, domain names and laptops carrying sensitive data. Once this core list is in place, move on to staff computers, printers and other devices.
Keeping it up to date
An inventory that is prepared once and left alone loses its reliability within a few months. The way to keep it current is to tie record-keeping to existing business steps: no new device is handed to a user before it is in the inventory, and when a device changes hands, goes for repair or is disposed of, the record is updated at the same time. For disposed devices, it should also be recorded that the data was securely erased or the disk destroyed.
Every three months, carry out a small reconciliation: compare the devices visible in a network scan with the inventory. A device on the network but not on the list may be equipment bought outside the normal process or an unrecognised connection. A device on the list that cannot be found points to loss, theft or an out-of-date record. Set calendar reminders for expiry dates too, leaving a few weeks of lead time for renewals and replacements.
Because an inventory contains information such as IP addresses, device versions and who holds administrator accounts, it is also a valuable map for someone with bad intentions. Restrict access to it and don't write passwords into the inventory; note only where passwords are stored. Keep a copy of the inventory somewhere that can be reached even when your systems are down.
Checklist
- Are computers, servers, mobile devices, network devices and external drives that carry data in the inventory?
- Are domain names, certificates, internet lines and cloud services recorded along with their account details?
- Are the serial number, user, location and warranty/support end date known for each device?
- Are installed software and versions collected automatically wherever possible?
- Is the inventory updated at the same time as purchase, issue, repair and disposal steps?
- Are network scan results compared with the inventory periodically?
- Are reminders set for warranty, subscription, domain name and certificate expiry?
- Is access to the inventory restricted, and is there a copy that can be reached when systems are down?