Diagnosing a school network with four complaints
St Nicholas is a secondary school in Hamrun with one computer lab of 28 workstations, 400 students and 35 staff sharing a single 100 Mbps fibre line and six wireless access points. Teachers report four problems. First, logging on at the start of a lesson takes between four and eight minutes, so a 45-minute lesson loses a fifth of its time. Second, students' saved work sometimes overwrites another student's file. Third, print jobs sit in a queue for ten minutes or come out of the wrong printer. Fourth, the deputy head says the whole network 'goes down' most mornings at about 10:30, around the time the office runs its daily backup to a USB drive attached to the file server. A quick look shows that classes share a single account, 'student', with the password written on the whiteboard, and that each pupil's user profile on the server already contains several hundred megabytes of photographs and videos.
1. Explain each of the four symptoms with a technical cause and a specific fix.
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Each symptom has a different cause and they should not be treated as one 'slow network'. (1) Four-to-eight-minute logons: pupils have roaming profiles holding hundreds of megabytes of photos and videos, so every logon copies the profile down. Fix: stop roaming the whole profile, redirect Documents and Desktop to a home folder on the server, apply disk quotas, and consider mandatory profiles for the lab. (2) Overwritten work: a shared 'student' account means every pupil writes to the same profile and folders. Fix: individual accounts with home directories and NTFS permissions that deny access to other pupils' folders. (3) Printing: jobs go to printers shared from individual PCs, so a queue depends on whether that PC happens to be switched on. Fix: a print server with proper per-printer queues, default printers assigned by group policy, and a held-queue release station if waste is high. (4) The 10:30 'outage': the USB backup attached to the file server saturates disk and network I/O and the server stops answering clients. Fix: back up to a separate device outside lesson hours, throttled, with a tested restore. The shared password is also an accountability and safeguarding failure, not merely an IT one, because no action can be attributed to a person.
2. Recommend how accounts and file storage should be restructured, giving reasons grounded in accountability and data protection.
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Accounts should be created per person: each pupil gets a username based on intake year plus a unique number, each member of staff a separate account, and generic accounts only where no personal data is involved. Pupils go into security groups by year and class, and group policy maps the correct home drive and shared resources, so a new pupil is configured by group membership rather than by hand. Home folders sit on a server share with permissions that allow the owner and administrators only; that permission boundary is what stops the overwriting seen now. Quotas, say 500 MB per pupil and 2 GB per teacher, keep profiles small and storage predictable, and stop a single video project filling the volume. Staff who need administrative rights should have a separate admin account, not browse as administrator all day. Passwords must not be written on a whiteboard, the shared 'student' account should be disabled, and leavers disabled on their last day. Because the school holds children's personal data, it needs a record of who accessed what, which shared credentials make impossible; access should be the minimum needed for the role.
3. The head proposes buying more wireless access points to fix the slowness. Evaluate that proposal.
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Adding access points addresses coverage and, at best, contention; it does not fix authentication, profile size, file permissions or disk input/output. The evidence points elsewhere: a slow logon is a domain-controller and profile-copying problem, and the 10:30 failure coincides with a backup rather than with any lesson pattern. Buying hardware first would spend money without removing a single one of the four symptoms, and could make matters worse because more access points on the same channels in a dense building increase co-channel interference unless the channels are planned (on 2.4 GHz, use 1, 6 and 11) and the 5 GHz band is used for capacity. A defensible plan is to measure first: logon timings before and after redirecting profiles, disk queue length on the server during the backup window, and a wireless signal and channel survey in each classroom at lesson time. Then fix the cheap causes - profiles, permissions, backup schedule, print server. Only then, if the survey shows genuine dead spots or too many clients per access point, add access points with a controller and a channel plan. The head should be told the cost of the purchase against the measured benefit, not against a feeling that the network is slow.