[{"data":1,"prerenderedAt":54},["ShallowReactive",2],{"$f3qygwji4alwpw":3},{"title":4,"seoTitle":5,"description":6,"route":7,"kind":8,"toolKey":9,"intro":10,"indexable":11,"sections":12,"related":51},"A 記錄與 CNAME：位址還是別名？","A 記錄與 CNAME：位址還是別名？ | nslookup.online","了解 A、AAAA 與 CNAME 差異、別名解析、共存規則及 DNS 與 HTTP 重新導向的區別。","\u002Fzh-tw\u002Fguides\u002Fa-record-vs-cname\u002F","guide",null,"兩類記錄解決不同命名問題，依服務目標選擇。",true,[13,20,27,33,39,45],{"id":14,"title":15,"paragraphs":16,"code":19},"address","A 與 AAAA 指定位址",[17,18],"A 對應 IPv4，AAAA 對應 IPv6，同名可有多位址，順序不代表唯一主要端點。","有穩定位址時可用位址記錄；若服務換位址，需更新記錄或供應商路由。","api.example.com. 300 IN A    192.0.2.10\napi.example.com. 300 IN AAAA 2001:db8::10\n\n僅為文件範例位址。",{"id":21,"title":22,"paragraphs":23,"code":26},"alias","CNAME 指向另一名稱",[24,25],"CNAME 將名稱設為另一 DNS 名稱的別名。查位址時需追蹤別名再取得目標 A\u002FAAAA。","服務商管理的名稱可隨位址遷移，別名避免複製當下 IP，但仍須依說明確認位置適合。","www.example.com. 300 IN CNAME edge.example.net.\nedge.example.net. 300 IN A    192.0.2.10\n\n僅為文件範例。",{"id":28,"title":29,"paragraphs":30},"coexistence","注意共存規則",[31,32],"一般 CNAME 通常不能與同名其他資料共存。根網域需 SOA、NS，普通 CNAME 通常不適合。","ALIAS、ANAME、flattening 為提供商功能，公開可回 A\u002FAAAA 而非 CNAME，勿以控制台名稱判斷。",{"id":34,"title":35,"paragraphs":36},"redirect","DNS 別名不是 HTTP 跳轉",[37,38],"CNAME 不改網址或路徑，瀏覽器仍對原主機名稱發 HTTP 請求，TLS 與 Host 也須符合。","HTTP 301\u002F302 由網頁伺服器回傳，可指另一 URL。搬遷網址需要相應 HTTP 設定，不只是 DNS。",{"id":40,"title":41,"paragraphs":42},"troubleshooting","謹慎追蹤鏈路",[43,44],"查準確 CNAME 再檢查目標。迴圈或中間故障使追蹤未完成；產品跳數上限不等於目標無效。","比較前匹配類型、名稱、解析器，別名與位址快取可分別到期，應記 TTL 而非固定傳播說法。",{"id":46,"title":47,"paragraphs":48},"choice","該發布哪種記錄",[49,50],"依服務商要求選擇。給 IP 要確認穩定性，給名稱要確認別名或根網域專用功能。","可行時先測試並保留回復設定。本站只讀公開 DNS，不改區域或證明應用可用。",[52,53],"\u002F","\u002Fcname-lookup\u002F",1792661399429]