Current Location： Blog >
South Korea server
1.
overview: network characteristics and common risks of kt station group
• kt has multiple backbone nodes in south korea, and the delay distribution is usually between 10-60ms;• a site group usually consists of multiple vps/dedicated servers, and public ip pools and port restrictions require attention;
• common risks: bandwidth burst, tcp half-open connection, dns resolution anomaly, cdn back-to-origin problem;
• monitoring recommendations: use snmp/netflow and delay monitoring, and the traffic sampling period is recommended to be 1 minute;
• alarm threshold example: traffic exceeding 500mbps or pps>500k triggers an advanced alarm.
2.
fault location process and tool list
• step 1: confirm the scope of impact (single machine/subnet/full site group), and group and investigate by ip segment;• step 2: link detection, use mtr/traceroute to confirm the hop count and packet loss rate;
• step 3: host-side monitoring, check top/iostat/netstat/ss output;
• step 4: packet capture analysis, tcpdump -i eth0 -c 20000 host xyzw;
• step 5: upstream verification, check cdn back-to-origin, dns resolution and kt peer alarm records.
3.
host/vps configuration and performance bottleneck examples
• recommended base configuration (example): 4 vcpu / 8gb ram / 100gb nvme / 1gbps port;• performance traps: single-core saturation, high io wait, and large proportion of softirqs;
• network parameter tuning: net.core.somaxconn=1024, net.ipv4.tcp_max_syn_backlog=2048;
• nginx recommendation: worker_processes=auto, worker_connections=4096;
• resource monitoring: when 95% of the time cpu load>number of cores or iowait>30%, expansion or optimization is required.
| host | cpu | memory | port bandwidth | typical traffic |
|---|---|---|---|---|
| vps-kr-01 | 4 vcpus | 8gb | 1gbps | average 120mbps, peak 600mbps |
| vps-kr-02 | 8 vcpus | 16 gb | 2gbps | average 300mbps, peak 1.2gbps |
4.
domain name/cdn/dns faqs and solutions
• dns resolution delays or errors: check ttls and upstream resolver connectivity;• domain name resolution is inconsistent: compare the results returned by authoritative dns and recursive dns;
• cdn return to origin timeout: check the return to origin ip whitelist and firewall policy;
• cache penetration: set appropriate caching rules for dynamic interfaces or use tokens to prevent brushing;
• recommendation: set up secondary back-to-origin and load balancing. the peak cdn bandwidth needs to be estimated to be 130% redundant.
5.
ddos defense strategy and recovery process
• identification characteristics: pps > 200k or traffic sudden increase > 300% in a short period of time are attack indicators;• local protection: use conntrack/iptables speed limit and syn cookies enabled;
• cloud/upstream: contact kt or a third party for cleaning (example cleaning capacity: 10gbps/100mpps);
• drill recommendations: regularly drill back-to-source switching, black hole routing and traffic cleaning switching;
• recovery steps: first cut off abnormal traffic (acl/black hole), then gradually release it and observe the manslaughter rate.
6.
examples of practical commands and log troubleshooting
• check the number of connections: ss -s and ss -tanp | grep syn | wc -l;• packet capture example: tcpdump -nn -s0 -c 10000 -w dump.pcap host 1.2.3.4;
• iptables speed limit example: iptables -a input -p tcp --syn -m limit --limit 50/s --limit-burst 100 -j accept;
• log inspection: /var/log/nginx/access.log counts request peaks by time window;
• performance data reference: in a fault, it was observed that pps increased from 30k to 680k, resulting in softirq accounting for 80%.
7.
real case: a certain kt station group was attacked by syn flood and the recovery process
• background: at 03:10 on 2025-03-12, the station group traffic suddenly increased from an average of 200mbps to 1.6gbps;• impact: connection queue overflow occurred on multiple vpss, and nginx 502/504 errors surged;
• disposal: immediately enable iptables speed limiting and request kt on the cdn side to assist in starting cleaning (10gbps cleaning node);
• recovery: return-to-origin traffic drops to normal within 15 minutes, manslaughter <0.5%, and business gradually recovers;
• lesson: it is recommended to retain at least 1:3 cleaning bandwidth budget and automated switching strategy all year round.
- Latest articles
- How To Save Money On Singapore VPS Vouchers Through Events And Promotions
- In Marketing And Data Scraping Scenarios, What Is The Most Appropriate Analysis Of Korean Native IP Proxies?
- Procurement References Korean Server Names, Quickly Filtering Brands From Supplier Catalogs
- Technical Implementation Detailed Steps For Binding And Routing Taiwan's Native Static Residential IPs
- Vietnam VPS Independent Server Long-term Maintenance Costs And Recommended Automated Operation And Maintenance Tools
- Optimization Suggestion: Storage Archiving And Resource Management Solution Under US VPS For Unlimited Content
- How To Purchase Gouyun Servers In Vietnam And Complete The Fast Launch Process
- How Is Japan's CN2 From An Operations And Maintenance Perspective? Recommendations For Handling Node And Routing Faults
- Hong Kong Cheap VPS Speed Review: Actual Bandwidth Peak And Stability Report
- Key Points Regarding Security Qualifications And Contract Terms For Companies That Can Choose Taiwanese Cloud Servers
- Popular tags
VPS Guide
User Guide
Security Compliance
Fault Handling
Instance
Backup
Remaining Life
Domain Name Registration
Start-up
Bandwidth Purchase
CN2
Advertising Speed
Self-built Data Centers
Vps Solution
Best Choice
Low Cost Migration
User Sharing
Tencent Cloud Malaysia Server
Independent Server
Cn2 Connection
Privacy Protection
Vps Configuration
Construction Process
Domain Name Security
Team Strategy
Bandwidth Management
Price-performance Ratio
Improve Website Access
Lag Reduction
Drones
Related Articles
-
Key Considerations Regarding Qualifications And Technical Support When Selecting A Service Provider For The CN2 Server Cluster In South Korea
This article summarizes the key considerations when selecting a service provider for the Korean CN2 server cluster, including their qualifications, as well as their network and hardware capabilities <b> CDN </b> and <b> DDoS Defense </b> Key aspects such as capabilities, operational support, and after-sales assistance are discussed, and DeXun Telecommunications is recommended as a preferred service provider. -
Review And Analysis Of The Current Situation Of Lol Korean Server In 2012
this article reviews and analysis of the current situation of lol korean servers in 2012, including the game environment, player mentality and future development trends. -
An Analysis Of The Liability In The Aftermath Of The Attack On The South Korean NPC Servers From A Legal And Compliance Perspective
From legal and compliance perspectives, five key questions are raised and answered regarding the attribution of responsibility following the hacking of the South Korean NPC servers. The analysis examines the division of criminal, civil, and compliance responsibilities, as well as key aspects of cross-border law enforcement and corporate governance.