How to deal with a traffic attack on the server? Steps and Precautions

at the moment of high-speed operation of Internet services, servers, as the core carrier of business bearers, face various network threats at any time, among which traffic attacks are the most common and highly destructive. Once such attacks are encountered, servers will respond slowly, service interruptions or even system crashes, which directly affect the normal operation of business and user experience. This article will detail the processing steps and key precautions after the server is attacked by traffic from multiple dimensions such as attack identification, emergency treatment, and long-term protection, so as to provide operation and maintenance personnel with a practical response plan.

How to quickly identify the server by traffic attack?

timely and accurate identification of the server traffic attack, is the premise of the follow-up disposal work, only accurately determine the type and scale of attacks, in order to take targeted measures.

1, monitoring indicators abnormal troubleshooting

focus on the server's bandwidth usage, CPU load, request volume and other core metrics, if the bandwidth suddenly spikes to the peak and continues to be high, CPU load far exceeds the daily threshold, or the request volume increases exponentially in a short period of time, it may be encountered by the server traffic attack. You can view data fluctuations in real time through cloud platform monitoring tools and system monitoring commands such as top and iftop that come with the server.

2, abnormal request characteristic analysis

check the access log of the server, if you find a large number of duplicate requests with the same source IP, single request path or meaningless request parameters, or a large number of forged user agent and Referer information, these are typical characteristics of the server being attacked by traffic. For example, common CC attacks consume server resources by sending a large number of legitimate requests, and the logs will show high-frequency duplicate request records.

two, the server is traffic attack emergency handling steps

confirm that the server is attacked by traffic, it is necessary to start the emergency treatment process immediately, quickly stop the loss, and avoid the expansion of the attack scope to cause more serious impact on the business.

1, enable protection tools to intercept attack traffic

if you use Cloud as a Service, you can open the DDoS high-defense IP, Web application firewall and other protection services provided by Cloud as a Service provider for the first time, and drain the attack traffic to the high-defense node for cleaning. After filtering out the malicious traffic, the normal traffic will be returned to the server. For self-built servers, firewall rules can be temporarily enabled to block abnormal IP segments and limit the request frequency of single IP.

2, adjust the server resource configuration

during the attack, you can temporarily upgrade the server's bandwidth, CPU, memory and other resources to improve the server's impact resistance and avoid direct service interruption due to resource exhaustion. At the same time, close the temporarily unnecessary services and ports on the server to reduce resource consumption and prioritize the limited resources to ensure the normal operation of the core business.

Long-term protection strategy for server traffic attacks

server traffic attack disposal can not only stay in the emergency stop loss stage, but also need to establish a long-term protection system to reduce the risk of re-attack from the root.

1, build a multi-level protection architecture

build a multi-layer protection system composed of CDN acceleration nodes, Web application firewall, DDoS high defense, and the server's own firewall. CDN can cache static resources, shunt user requests to edge nodes, and reduce the pressure on the source server; Web application firewall can intercept SQL injection, XSS and other application layer attacks; DDoS high defense is specially designed to deal with network layer attacks with large traffic, and multi-dimensional resistance to the threat of server traffic attacks.

2, optimize server system configuration

regularly update and upgrade the server system to fix known security bugs; reasonably configure system parameters, such as adjusting the TCP connection timeout time, limiting the number of concurrent connections, to avoid the server due to a large number of invalid connections depletion of resources; at the same time, the access to the server Strict control, disable unnecessary accounts, set complex login passwords to prevent attackers from launching traffic attacks after invading the server through weak passwords.

4, the server is attacked by traffic recovery and optimization

every server traffic attack is an opportunity to improve protection capabilities, through post-mortem review, can summarize lessons learned, improve the follow-up protection program.

1, the attack process full link review

sort out the complete timeline of the server's traffic attack, including the time of the attack, the peak of the attack traffic, the type of attack, the effective time and effect of the protective measures, etc., and analyze the shortcomings in the attack disposal process, such as whether the monitoring and early warning are timely, whether the protective measures are in place, and whether the resource allocation is sufficient.

2, protection program targeted optimization

according to the results of the review, to adjust and optimize the existing protection strategies, such as monitoring blind spots exposed to this attack, new monitoring indicators and warning thresholds corresponding to; if found that the effect of a certain type of protection tool is not good, can replace more suitable products or adjust its rules configuration; at the same time, the organization of operation and maintenance personnel to carry out targeted emergency drills, improve the team response speed and disposal ability to deal with server traffic attacks.

To sum up, dealing with server traffic attacks is a systematic work, which needs to form a complete closed loop from rapid identification, emergency treatment, long-term protection to post-mortem review. Operation and maintenance personnel should always pay attention to the running status of the server, master scientific identification and disposal methods, and establish a sound protection system to effectively reduce the losses caused by attacks and ensure the continuous and stable operation of the business.