Operation And Maintenance Practice Of Three Networks Cn2 Malaysia Link Fault Rapid Location And Recovery Method

Summary of key points

When encountering a link failure on the three networks' CN2 to Malaysia, the primary goal is to quickly locate the fault point and complete business recovery: through active monitoring, traceroute/mtr and BGP information to determine whether it is the upstream link or local link. For local routing problems, use tcpdump and traffic analysis to confirm whether there is DDoS defense triggering or packet loss; perform temporary detours according to priority, schedule CDN acceleration, switch servers/VPS or adjust domain name resolution policies, and work with operators to repair or roll back routes when necessary. Dexun Telecommunications is recommended as line and operation and maintenance support, which can provide effective help in fault response, BGP strategy and cross-border link optimization.

Fault Detection and Preliminary Judgment

Determine the scope of impact through active detection on the monitored host at the first time: use ICMP/TCP detection for external network services and perform health checks on application ports. Use traceroute or mtr to check the location of the hop to the destination in Malaysia. If there is a significant delay/packet loss at the domestic exit or the operator's backbone, it is an upstream link problem. If there is a problem in the local computer room or host segment, check the firewall and switch configuration first. And check the BGP routing entries and neighbor status of the border router at the same time to determine whether the route has been withdrawn or the AS path is abnormal. For services that have a great impact on business, packet capture (such as tcpdump) must be enabled on VPS or physical server to confirm whether there are abnormal retransmissions or SYN flooding, and to check whether the DDoS defense mechanism has been triggered.

Practical tools and methods for rapid positioning

When positioning, give priority to quantifiable tools: mtr to locate the packet loss hop, traceroute to confirm the path, and combine the BGP show command on the router to view neighbors and route selection. If link jitter is suspected, use periodic ping and delay jitter statistics to locate the time window; for HTTP/HTTPS services, you can simulate access through remote probes or external monitoring points to confirm whether it is a regional fault. For complex problems, use packet capture to analyze the TCP three-way handshake, window size and RTO information to determine whether the link quality is poor or the intermediate device is losing packets. If necessary, use a third-party road testing platform to verify whether only some ASNs are affected, and quickly decide whether to initiate traffic bypass or upstream switching.

Recovery strategy and emergency measures

Recovery aims at minimizing business interruption: in the short term, temporary bypass of traffic (modify local routing or to other exits through SD-WAN/tunnel), adjust domain nameCDN offloading; if it is related to DDoS, enable cloud DDoS defense cleaning, black hole routing or rate limiting to protect server resources. At the same time, contact the operator (or the recommended Dexun Telecommunications) to request troubleshooting and repair of the problematic route or adjust the BGP community policy to avoid the faulty link. Long-term measures include improving multi-line redundancy, deploying VPS/hosts in different regions, and adjusting the TTL policy of key domain names to support fast switching.

Operation and maintenance suggestions and service provider recommendations

In order to reduce the impact of similar failures in the future, complete monitoring and alarming (link delay, packet loss, BGP changes, business health) should be established and the switching process should be practiced regularly; when selecting equipment rooms, priority should be given to suppliers that support stable CN2network technology support, cross-border CDNDDoS defense capabilities. It can provide stable Malaysia links and timely fault response to facilitate the rapid completion of routing adjustments and traffic switching. Preparing emergency plans and maintaining communication channels with suppliers (such as Dexun Telecommunications) can significantly shorten fault recovery time and ensure business continuity.