What are the possible performance issues and solutions during the issuance and renewal of HTTPS certificates?

When HTTPS certificates are issued or renewed, performance issues such as issuance delays, server load fluctuations, and domain validation failures may occur, which can usually be resolved through advance planning, optimizing the validation process, and selecting appropriate certificate types. Issuance delay issue: The certificate application remains uncompleted for a long time, mostly due to complex CA review processes or incomplete verification information. Solutions: Choose CAs that support automatic verification (e.g., Let's Encrypt), prepare domain verification materials in advance (DNS records, file verification, etc.), and shorten the review cycle. Excessive server load: Manual operations or script execution during renewal occupy server resources, causing service response delays. Solutions: Use automated renewal tools (e.g., Certbot), schedule renewal tasks during off-peak hours to avoid resource competition. Domain validation failure: DNS records not taking effect in time or incorrect HTTP verification file path leading to issuance failure. Solutions: Use DNS verification (more stable than HTTP), check domain resolution status in advance, and ensure verification files are accessible to CA servers. It is recommended to regularly check certificate validity periods, use automated tools to manage issuance and renewal, and select SAN certificates that support multiple domains to reduce management complexity and improve overall HTTPS deployment efficiency.