Singapore servers can be professionally cleaned for performance optimization and security hardening purposes. A professional server cleaning is far more than a simple disk cleaning or service restart, but requires a combination of system tuning, vulnerability repair, log audit and compliance check systems engineering.

The first rule of any cleaning operation is to avoid service interruption and data loss. Before you can touch the command line, you must complete the following preparations.

Use BorgBackup or Restic for de-encrypting backups to ensure fast rollback:

borg create /backup::$(date +%F) /var/www /etc /home  

After verifying the integrity of the backup, upload the snapshot to a remote storage (such as AWS S3 Singapore region) and record the SHA256 verification value of the backup file.

72-hour performance data is collected from Prometheus+Node Exporter, recording base values of CPU, memory, disk IO, and network traffic. Key indicators include the average disk queue depth (avgqusz), memory Swap usage, and TCP retransmission rate (retrans/s).

In accordance with the requirements of the Personal Data Protection Act (PDPA) of Singapore, the cleaning process does not involve the residue of user privacy data. Use grep r "NRIC" /data to scan for sensitive information such as ID numbers.

Performance cleaning from kernel parameters to service granularity optimization. File system optimization in storage tier cleaning, Ext4 file system performs online defragmentation:

e4defrag /var/lib/mysql  

For the XFS system, run the xfs_db command to analyze the fragmentation rate. If the fragment rate is higher than 30%, uninstall the system and run the xfs_fsr command.

Log rotation policy: Configure logrotate to adjust the cutting frequency based on service loads to prevent a single log file from exceeding 10GB.

conf  
/var/log/nginx/.log {  
daily  
rotate 14  
compress  
delaycompress  
missingok  
notifempty  
sharedscripts  
postrotate  
nginx s reopen  
endscript  
}  

Memory and process management, zombie process cleaning

ps A ostat,ppid | grep e '^[Zz]' | awk '{print $2}' | xargs kill 9  

Transparent large page (THP) Disable editing /etc/sysctl.conf:

conf  
vm.nr_overcommit_hugepages = 0  

Network stack tuning, optimizing TCP stack for high concurrency scenarios:

conf  
net.core.somaxconn = 65535  
net.ipv4.tcp_tw_reuse = 1  
net.ipv4.tcp_fin_timeout = 15  

Safe cleaning from surface elimination to depth defense

1. Scan malicious code

Depth inspection using ClamAV combined with YARA rules:

freshclam Updated the virus library
clamscan r bell i /  

When suspicious files are found, strace tracks their behavior and generates a process tree.

2. Permission system reconstruction

Reset SSH key:

rm /etc/ssh/ssh_host_ && dpkgreconfigure opensshserver  

Implement the principle of least authority:

find/type f perm /4000 ls Searches for the abnormal SUID file

3. Closed loop management of vulnerabilities

Perform vulnerability scanning using OpenVAS or Nessus, focusing on:

Unfixed Remote Code Execution (RCE) vulnerabilities, outdated SSL/TLS protocol support, weak password policies (detected using john wordlist=rockyou.txt shadow), compliance hardening to PDPA and CSA standards.

1. Data lifecycle management

Safely erase obsolete disks with shred:

shred n 7 z v /dev/sdb  

Encrypt temporary swap partition:

cryptsetup luksFormat /dev/sdc1  

2. Configure audit logs

Enable the Linux auditd service to record critical events:

conf  
a always,exit F arch=b64 S execve k process_trace  
w /etc/passwd p wa k identity  

3. Network isolation policies

Implement VLAN division to isolate management traffic and service traffic. Use WireGuard to build an encrypted management channel instead of the traditional SSH direct connection. After cleaning, the effect converges from the performance benchmark to the attack surface. After the cleaning is completed, a triple verification is required to ensure effectiveness. Apache Bench was used in the performance regression test to compare QPS before and after cleaning:

ab n 100000 c 500 http://localhost:80/test  

Simulate penetration testing with OWASP ZAP or Burp Suite, focusing on unauthorized API endpoints and sensitive information leaks (such as.git directory exposure). Generate CSA STAR compliant audit reports covering proof of data storage location (within Singapore only), encryption algorithm strength (AES256, RSA2048 onwards).

Deep cleaning of a server is like delicate surgery, both cutting out the lesions (redundant data, malicious code) and reconfiguring the immune system (security policies, performance configurations). Under Singapore's strict data governance framework, technicians are required to have both a system-level global vision and atomic-level operational precision. Every successful cleaning is not only a refresh of hardware resources, but also a strategic upgrade of network offensive and defensive capabilities - only by transforming the cleaning process into a closed loop of continuous improvement can an unbreakable city be built in the digital flood.