{"id":33436,"date":"2026-09-29T10:00:00","date_gmt":"2026-09-29T02:00:00","guid":{"rendered":"https:\/\/cn.hostease.com\/blog\/?p=33436"},"modified":"2026-10-08T10:57:11","modified_gmt":"2026-10-08T02:57:11","slug":"cloud-server-mtu-network","status":"publish","type":"post","link":"https:\/\/cn.hostease.com\/blog\/guides\/cloud-server-mtu-network\/","title":{"rendered":"\u4e91\u670d\u52a1\u5668 MTU \u8c03\u6574\uff1a\u5bb9\u5668\u7f51\u7edc\u4e0e\u96a7\u9053\u573a\u666f\u7684\u5206\u7247\u6392\u67e5"},"content":{"rendered":"<p>\u4f60\u53ef\u80fd\u9047\u5230\u8fc7\u8fd9\u6837\u7684\u602a\u73b0\u8c61\uff1a\u5c0f\u5305 ping \u5f97\u901a\uff0cSSH \u4e5f\u80fd\u767b\u5f55\uff0c\u4f46\u7f51\u9875\u6253\u4e0d\u5f00\u3001\u955c\u50cf\u62c9\u53d6\u5361\u5728\u534a\u8def\u3001\u6587\u4ef6\u4f20\u5230\u4e00\u534a\u5c31\u505c\u4f4f\u3002\u8fd9\u7c7b&#8221;\u80fd\u8fde\u4e0d\u4e0a\u7f51&#8221;\u7684\u75c7\u72b6\uff0c\u5341\u6709\u516b\u4e5d\u548c MTU\uff08\u6700\u5927\u4f20\u8f93\u5355\u5143\uff09\u6709\u5173\u3002\u4e91\u670d\u52a1\u5668\uff08\u57fa\u4e8e\u865a\u62df\u5316\u6280\u672f\u7684\u5f39\u6027\u670d\u52a1\u5668\uff09\u4e0a\u7684\u5bb9\u5668\u7f51\u7edc\u548c\u96a7\u9053\u4f1a\u989d\u5916\u5c01\u88c5\u534f\u8bae\u5934\u90e8\uff0c\u8ba9\u5b9e\u9645\u53ef\u7528\u7684\u62a5\u6587\u7a7a\u95f4\u53d8\u5c0f\uff0c\u4e00\u65e6\u67d0\u4e2a\u73af\u8282\u6ca1\u6709\u540c\u6b65\u8c03\u6574 MTU\uff0c\u5927\u5305\u5c31\u4f1a\u88ab\u4e22\u5f03\u6216\u5206\u7247\uff0c\u4e1a\u52a1\u8868\u73b0\u4e3a\u95f4\u6b47\u6027\u8d85\u65f6\u3002\u672c\u6587\u6559\u4f60\u5982\u4f55\u5b9a\u4f4d\u8fd9\u7c7b\u5206\u7247\u95ee\u9898\uff0c\u5e76\u7ed9\u51fa\u53ef\u4ee5\u7167\u7740\u6267\u884c\u7684\u8c03\u6574\u548c\u9a8c\u8bc1\u6b65\u9aa4\u3002<\/p>\n<h2>\u4e3a\u4ec0\u4e48\u96a7\u9053\u548c\u5bb9\u5668\u7f51\u7edc\u5bb9\u6613\u89e6\u53d1\u5206\u7247\u95ee\u9898<\/h2>\n<p>\u6807\u51c6\u4ee5\u592a\u7f51\u7684 MTU \u662f 1500 \u5b57\u8282\uff0c\u5373\u5355\u4e2a\u62a5\u6587\u6700\u591a\u643a\u5e26 1500 \u5b57\u8282\u7684\u8d1f\u8f7d\u3002\u8fd9\u4e2a\u6570\u503c\u5047\u8bbe\u62a5\u6587\u4ee5\u539f\u59cb\u5f62\u6001\u76f4\u63a5\u5728\u7269\u7406\u94fe\u8def\u4e0a\u4f20\u8f93\u3002\u4f46\u4e91\u670d\u52a1\u5668\u7684\u4e24\u7c7b\u5e38\u89c1\u67b6\u6784\u4f1a\u6253\u7834\u8fd9\u4e2a\u5047\u8bbe\uff1a<\/p>\n<p><strong>\u96a7\u9053\u5c01\u88c5<\/strong>\u3002VPN\uff08\u865a\u62df\u4e13\u7528\u7f51\u7edc\uff09\u3001GRE\u3001VXLAN\u3001WireGuard \u7b49\u96a7\u9053\u6280\u672f\u4f1a\u5728\u539f\u59cb\u62a5\u6587\u5916\u9762\u518d\u5305\u4e00\u5c42\u534f\u8bae\u5934\u3002\u4ee5 VXLAN \u4e3a\u4f8b\uff0c\u5916\u5c42\u5c01\u88c5\u8981\u6d88\u8017 50 \u5b57\u8282\u5de6\u53f3\uff0c\u5982\u679c\u5185\u5c42\u4ecd\u6309 1500 \u5b57\u8282\u53d1\u9001\uff0c\u52a0\u4e0a\u5c01\u88c5\u540e\u5c31\u662f 1550 \u5b57\u8282\uff0c\u8d85\u8fc7\u4e86\u7269\u7406\u94fe\u8def\u7684 1500 \u4e0a\u9650\uff0c\u8def\u7531\u5668\u53ea\u80fd\u5206\u7247\u6216\u76f4\u63a5\u4e22\u5f03\u3002\u5f00\u542f\u4e86&#8221;\u4e0d\u8981\u5206\u7247&#8221;\u6807\u5fd7\u7684\u62a5\u6587\u4f1a\u88ab\u76f4\u63a5\u4e22\u5f03\uff0c\u540c\u65f6\u56de\u9001\u4e00\u6761 ICMP\uff08\u4e92\u8054\u7f51\u63a7\u5236\u62a5\u6587\u534f\u8bae\uff09&#8221;\u9700\u8981\u5206\u7247&#8221;\u9519\u8bef\u2014\u2014\u800c\u5f88\u591a\u4e91\u73af\u5883\u7684\u5b89\u5168\u7ec4\u9ed8\u8ba4\u62e6\u622a ICMP\uff0c\u5bfc\u81f4\u53d1\u9001\u65b9\u6536\u4e0d\u5230\u9000\u56de\u7684\u62a5\u6587\uff0c\u53ea\u80fd\u5e72\u7b49\u8d85\u65f6\u3002<\/p>\n<p><strong>\u5bb9\u5668\u865a\u62df\u7f51\u7edc<\/strong>\u3002Docker \u9ed8\u8ba4\u7684 bridge \u7f51\u7edc\u3001Kubernetes \u7684\u591a\u6570 CNI\uff08\u5bb9\u5668\u7f51\u7edc\u63a5\u53e3\uff09\u63d2\u4ef6\u3001\u4ee5\u53ca\u670d\u52a1\u7f51\u683c\u7684 sidecar \u4ee3\u7406\uff0c\u90fd\u4f1a\u5728\u62a5\u6587\u8def\u5f84\u4e0a\u589e\u52a0\u5c01\u88c5\u6216\u8f6c\u6362\u5c42\u3002\u4e00\u4e2a Pod\uff08\u5bb9\u5668\u7ec4\uff09\u53d1\u51fa\u7684\u62a5\u6587\uff0c\u5230\u8fbe\u7269\u7406\u7f51\u5361\u65f6\u53ef\u80fd\u5df2\u7ecf\u7ecf\u8fc7 veth pair\u3001bridge\u3001overlay \u5c01\u88c5\u4e09\u9053\u5904\u7406\uff0c\u6bcf\u4e00\u9053\u90fd\u53ef\u80fd\u6539\u53d8\u62a5\u6587\u5927\u5c0f\u3002\u8de8\u8282\u70b9\u901a\u4fe1\u8d70 overlay \u7f51\u7edc\u65f6\u5c24\u5176\u660e\u663e\uff1a\u7269\u7406\u7f51\u5361 MTU 1500\uff0coverlay \u7f51\u7edc\u7684 MTU \u5fc5\u987b\u76f8\u5e94\u4e0b\u8c03\uff0c\u5426\u5219\u8de8\u8282\u70b9\u7684\u5927\u8bf7\u6c42\u5168\u90e8\u5931\u8d25\uff0c\u800c\u540c\u8282\u70b9\u901a\u4fe1\u5374\u4e00\u5207\u6b63\u5e38\u3002<\/p>\n<p>\u5224\u65ad\u662f\u5426\u5c5e\u4e8e MTU \u95ee\u9898\u6709\u4e2a\u5feb\u901f\u65b9\u6cd5\uff1a\u7528 ping \u7684\u5927\u5305\u6a21\u5f0f\u6d4b\u8bd5\u3002<code>ping -M do -s 1472 \u76ee\u6807\u5730\u5740<\/code> \u4e2d\uff0c<code>-M do<\/code> \u8868\u793a\u7981\u6b62\u5206\u7247\uff0c<code>-s 1472<\/code> \u8868\u793a\u8d1f\u8f7d 1472 \u5b57\u8282\uff081472 + 28 \u5b57\u8282\u7684 IP\/ICMP \u5934\u6b63\u597d\u662f 1500\uff09\u3002\u5982\u679c\u8fd9\u4e2a\u547d\u4ee4\u6210\u529f\u800c <code>-s 1473<\/code> \u5931\u8d25\uff0c\u8bf4\u660e\u8def\u5f84 MTU \u5c31\u662f 1500\uff1b\u5982\u679c 1472 \u90fd\u5931\u8d25\uff0c\u8bf4\u660e\u4e2d\u95f4\u6709\u96a7\u9053\u6216\u5c01\u88c5\u5728\u5403\u6389\u62a5\u6587\u7a7a\u95f4\u3002\u8fd9\u7c7b\u95ee\u9898\u5e38\u51fa\u73b0\u5728<a href=\"https:\/\/cn.hostease.com\/blog\/server\/\">\u670d\u52a1\u5668\u914d\u7f6e<\/a>\u73af\u8282\uff0c\u5efa\u8bae\u5728\u90e8\u7f72\u96a7\u9053\u6216\u5bb9\u5668\u96c6\u7fa4\u4e4b\u524d\u5c31\u628a MTU \u7eb3\u5165\u521d\u59cb\u5316\u6e05\u5355\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/cn.hostease.com\/blog\/wp-content\/uploads\/2026\/10\/cloud-server-mtu-network-cover.webp\" alt=\"\u4e91\u670d\u52a1\u5668 MTU \u8c03\u6574\u5c01\u9762\u914d\u56fe\uff1a\u96a7\u9053\u5c01\u88c5\u5bfc\u81f4\u62a5\u6587\u8d85\u8fc7\u94fe\u8def\u4e0a\u9650\u7684\u793a\u610f\" loading=\"lazy\" \/><\/p>\n<h2>\u5982\u4f55\u9010\u5c42\u5b9a\u4f4d MTU \u4e0d\u5339\u914d\u7684\u4f4d\u7f6e<\/h2>\n<p>\u5b9a\u4f4d\u7684\u6838\u5fc3\u601d\u8def\u662f&#8221;\u4e8c\u5206\u63a2\u6d4b&#8221;\uff1a\u5148\u786e\u5b9a\u7aef\u5230\u7aef\u7684\u8def\u5f84 MTU\uff08PMTU\uff0c\u8def\u5f84\u6700\u5927\u4f20\u8f93\u5355\u5143\uff09\uff0c\u518d\u9010\u8df3\u7f29\u5c0f\u8303\u56f4\u627e\u51fa\u5403\u6389\u62a5\u6587\u7684\u73af\u8282\u3002<\/p>\n<p><strong>\u7b2c\u4e00\u6b65\uff1a\u6d4b\u51fa\u6574\u6761\u8def\u5f84\u7684\u6700\u5c0f MTU\u3002<\/strong> \u5728\u4e91\u670d\u52a1\u5668\u4e0a\u6267\u884c\uff1a<\/p>\n<pre><code class=\"language-bash\"># \u4ece\u5c0f\u5230\u5927\u4e8c\u5206\u6d4b\u8bd5\uff0c\u627e\u5230\u80fd\u901a\u8fc7\u7684\u6700\u5927\u8d1f\u8f7d\u503c\nping -M do -s 1472 \u76ee\u6807\u5730\u5740\nping -M do -s 1400 \u76ee\u6807\u5730\u5740\nping -M do -s 1300 \u76ee\u6807\u5730\u5740\n<\/code><\/pre>\n<p>\u5047\u8bbe <code>-s 1472<\/code> \u5931\u8d25\u3001<code>-s 1400<\/code> \u6210\u529f\uff0c\u5219\u8def\u5f84 MTU \u5728 1428 \u5230 1500 \u4e4b\u95f4\u3002\u7ee7\u7eed\u5728\u533a\u95f4\u5185\u4e8c\u5206\uff0c\u51e0\u5206\u949f\u5c31\u80fd\u9501\u5b9a\u7cbe\u786e\u503c\u3002\u8d1f\u8f7d\u503c\u52a0 28\uff08IPv4 \u5934 20 \u5b57\u8282 + ICMP \u5934 8 \u5b57\u8282\uff09\u5c31\u662f\u8def\u5f84 MTU\u3002\u7f51\u7edc\u5c42\u6392\u67e5\u4e0e <a href=\"https:\/\/cn.hostease.com\/blog\/guides\/ttfb-hosting-optimization\/\">TTFB \u4e0e\u4e3b\u673a\u4f18\u5316<\/a>\u7684\u601d\u8def\u76f8\u901a\uff1a\u5148\u628a\u4f20\u8f93\u8def\u5f84\u4e0a\u7684\u74f6\u9888\u91cf\u5316\uff0c\u518d\u52a8\u624b\u8c03\u6574\u3002<\/p>\n<p><strong>\u7b2c\u4e8c\u6b65\uff1a\u533a\u5206\u672c\u673a\u95ee\u9898\u8fd8\u662f\u8def\u5f84\u95ee\u9898\u3002<\/strong> \u5728\u540c\u4e00\u53f0\u670d\u52a1\u5668\u4e0a\u5bf9\u591a\u4e2a\u4e0d\u540c\u76ee\u6807\u6267\u884c\u4e0a\u9762\u7684\u6d4b\u8bd5\u3002\u5982\u679c\u6240\u6709\u76ee\u6807\u7684\u6700\u5927\u53ef\u7528\u8d1f\u8f7d\u4e00\u81f4\u504f\u4f4e\uff0c\u95ee\u9898\u5927\u6982\u7387\u5728\u672c\u673a\u7684\u96a7\u9053\u6216\u5bb9\u5668\u63a5\u53e3\u914d\u7f6e\uff1b\u5982\u679c\u53ea\u6709\u7279\u5b9a\u76ee\u6807\u504f\u4f4e\uff0c\u95ee\u9898\u5728\u5bf9\u7aef\u6216\u4e2d\u95f4\u94fe\u8def\u3002<\/p>\n<p><strong>\u7b2c\u4e09\u6b65\uff1a\u68c0\u67e5\u63a5\u53e3\u914d\u7f6e\u3002<\/strong> \u7528 <code>ip link show<\/code> \u9010\u4e2a\u67e5\u770b\u7f51\u5361\u3001\u96a7\u9053\u53e3\u3001\u5bb9\u5668 veth \u7684 MTU \u503c\uff1a<\/p>\n<pre><code class=\"language-bash\">ip link show\n# \u91cd\u70b9\u5173\u6ce8\u8fd9\u4e9b\u63a5\u53e3\u7684 mtu \u5b57\u6bb5\n# eth0: mtu 1500\uff08\u7269\u7406\u7f51\u5361\uff09\n# wg0 \/ tun0 \/ flannel.1 \/ vxlan.calico: mtu 1420 \u6216\u5176\u4ed6\n# vethxxxx: mtu 1500 \u6216\u4e0e\u5bb9\u5668\u4fa7\u4e0d\u4e00\u81f4\n<\/code><\/pre>\n<p>\u5e38\u89c1\u7684\u4e0d\u5339\u914d\u6a21\u5f0f\uff1a\u5bb9\u5668\u5185 eth0 \u7684 MTU \u662f 1500\uff0c\u4f46\u5bbf\u4e3b\u673a overlay \u63a5\u53e3\u662f 1450\uff0c\u5bb9\u5668\u53d1\u51fa\u7684 1500 \u5b57\u8282\u5927\u5305\u5728 overlay \u5c01\u88c5\u540e\u8d85\u9650\u3002\u8fd9\u65f6\u8981\u4e48\u628a\u5bb9\u5668\u7f51\u7edc\u6574\u4f53\u4e0b\u8c03\u5230 1450\uff0c\u8981\u4e48\u5728\u5bbf\u4e3b\u673a\u5f00\u542f\u5c01\u88c5\u534f\u8bae\u5bf9\u5e94\u7684\u534f\u5546\u673a\u5236\u3002<\/p>\n<p><strong>\u7b2c\u56db\u6b65\uff1a\u6293\u5305\u786e\u8ba4\u4e22\u5f03\u70b9\u3002<\/strong> \u5982\u679c\u4ee5\u4e0a\u8fd8\u4e0d\u80fd\u5b9a\u4f4d\uff0c\u5728\u4e24\u7aef\u540c\u65f6\u7528 tcpdump\uff08\u7f51\u7edc\u6293\u5305\u5de5\u5177\uff09\u89c2\u5bdf\uff1a<\/p>\n<pre><code class=\"language-bash\">tcpdump -ni eth0 'icmp[type=3 code=4]'   # \u76d1\u542c&quot;\u9700\u8981\u5206\u7247&quot;\u7684 ICMP \u9519\u8bef\ntcpdump -ni eth0 '(ip[6:2] &amp; 0x2000 != 0)'  # \u76d1\u542c\u5e26\u4e0d\u5206\u7247\u6807\u5fd7\u7684\u5927\u5305\n<\/code><\/pre>\n<p>\u5982\u679c\u672c\u673a\u53d1\u51fa\u5927\u5305\u540e\u53ea\u770b\u5230\u5bf9\u65b9\u56de\u7684&#8221;\u9700\u8981\u5206\u7247&#8221;\u9519\u8bef\u88ab\u5b89\u5168\u7ec4\u62e6\u6389\u3001\u6216\u6839\u672c\u6ca1\u6709\u54cd\u5e94\uff0c\u5c31\u80fd\u786e\u8ba4\u662f\u4e2d\u95f4\u8bbe\u5907\u4e22\u5f03\u800c\u975e\u5e94\u7528\u5c42\u95ee\u9898\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/cn.hostease.com\/blog\/wp-content\/uploads\/2026\/10\/cloud-server-mtu-network-probe.webp\" alt=\"\u7528\u5927\u5305 ping \u9010\u7ea7\u6d4b\u8bd5\u8def\u5f84 MTU \u7684\u793a\u610f\" loading=\"lazy\" \/><\/p>\n<h2>\u5bb9\u5668\u7f51\u7edc\u7684 MTU \u8c03\u6574\u65b9\u6848<\/h2>\n<p>\u5b9a\u4f4d\u5230\u5bb9\u5668\u7f51\u7edc\u540e\uff0c\u6309\u5bbf\u4e3b\u673a overlay \u63a5\u53e3\u7684\u5b9e\u9645 MTU \u6765\u7edf\u4e00\u8c03\u6574\u3002\u539f\u5219\u662f\uff1a\u5bb9\u5668\u5185 MTU \u2264 \u5bbf\u4e3b\u673a overlay \u63a5\u53e3 MTU \u2265 \u7269\u7406 MTU \u51cf\u53bb\u5c01\u88c5\u5f00\u9500\u3002<\/p>\n<p><strong>Docker \u573a\u666f<\/strong>\u3002\u4fee\u6539 <code>\/etc\/docker\/daemon.json<\/code>\uff0c\u52a0\u5165\u5168\u5c40\u914d\u7f6e\u540e\u91cd\u542f Docker \u670d\u52a1\uff1a<\/p>\n<pre><code class=\"language-json\">{\n  &quot;mtu&quot;: 1450\n}\n<\/code><\/pre>\n<p>\u6ce8\u610f\u91cd\u542f Docker \u4f1a\u91cd\u5efa\u9ed8\u8ba4 bridge \u7f51\u7edc\u5e76\u77ed\u6682\u4e2d\u65ad\u5bb9\u5668\u7f51\u7edc\uff0c\u751f\u4ea7\u73af\u5883\u5e94\u5728\u7ef4\u62a4\u7a97\u53e3\u64cd\u4f5c\u3002\u5bf9\u81ea\u5b9a\u4e49 bridge \u7f51\u7edc\uff0c\u53ef\u4ee5\u5728 <code>docker network create<\/code> \u65f6\u7528 <code>--opt com.docker.network.driver.mtu=1450<\/code> \u5355\u72ec\u6307\u5b9a\u3002\u5df2\u8fd0\u884c\u4e2d\u7684\u5bb9\u5668\u4e0d\u4f1a\u81ea\u52a8\u751f\u6548\uff0c\u9700\u8981\u91cd\u5efa\u3002<\/p>\n<p><strong>Kubernetes \u573a\u666f<\/strong>\u3002CNI \u63d2\u4ef6\u4e0d\u540c\uff0c\u914d\u7f6e\u4f4d\u7f6e\u4e5f\u4e0d\u540c\u3002Calico \u5728\u5b89\u88c5\u914d\u7f6e\u4e2d\u8bbe\u7f6e <code>vxlanMTU<\/code> \u6216 <code>ipipMTU<\/code>\uff1bFlannel \u7684 <code>net-conf.json<\/code> \u91cc\u5199 <code>mtu<\/code> \u5b57\u6bb5\uff1bCilium \u76f4\u63a5\u5728 ConfigMap \u4e2d\u6307\u5b9a\u3002\u914d\u7f6e\u751f\u6548\u540e\u65b0\u8c03\u5ea6\u7684 Pod \u4f1a\u62ff\u5230\u65b0\u7684 MTU\uff0c\u5b58\u91cf Pod \u9700\u8981\u6eda\u52a8\u91cd\u5efa\u3002\u96c6\u7fa4\u5c42\u9762\u7684\u7ecf\u9a8c\u503c\uff1aVXLAN \u5c01\u88c5\u6309\u7269\u7406 MTU \u51cf 50 \u914d\u7f6e\uff0cIPIP \u51cf 20\uff0cWireGuard \u51cf 60 \u5230 80\uff08\u89c6\u52a0\u5bc6\u5957\u4ef6\u800c\u5b9a\uff09\u3002<\/p>\n<p>\u8c03\u6574\u540e\u7684\u9a8c\u8bc1\u4e0d\u8981\u53ea\u770b ping\u3002\u7528 <code>ip link show<\/code> \u786e\u8ba4\u5bb9\u5668\u5185\u63a5\u53e3\u503c\uff0c\u518d\u7528\u5927\u5305 ping \u9a8c\u8bc1\u8de8\u8282\u70b9\u8def\u5f84\uff0c\u6700\u540e\u7528\u771f\u5b9e\u4e1a\u52a1\u6d41\u91cf\uff08\u5982\u62c9\u53d6\u955c\u50cf\u3001\u4e0b\u8f7d\u5927\u6587\u4ef6\uff09\u786e\u8ba4\u7a33\u5b9a\u3002\u6709\u4e00\u4e2a\u5bb9\u6613\u5ffd\u7565\u7684\u7ec6\u8282\uff1a\u67d0\u4e9b\u5e94\u7528\u5c42\u534f\u8bae\uff08\u5982 PMTUD\uff0c\u8def\u5f84 MTU \u53d1\u73b0\u4f9d\u8d56 ICMP \u56de\u5305\uff09\u5728\u5b89\u5168\u7ec4\u62e6\u622a ICMP \u65f6\u4f1a\u9000\u5316\uff0c\u53ef\u4ee5\u5728\u4e91\u5e73\u53f0\u5b89\u5168\u7ec4\u4e2d\u653e\u884c ICMP type 3 code 4\uff0c\u8fd9\u662f\u4e13\u95e8\u7528\u4e8e&#8221;\u9700\u8981\u5206\u7247&#8221;\u901a\u77e5\u7684\u62a5\u6587\uff0c\u653e\u884c\u5b83\u4e0d\u4f1a\u5e26\u6765\u989d\u5916\u98ce\u9669\u3002\u5982\u679c\u4f60\u7684\u4e1a\u52a1\u540c\u65f6\u4f9d\u8d56\u7ad9\u70b9\u8bbf\u95ee\u901f\u5ea6\uff0c\u7f51\u7edc\u5c42\u4fee\u590d\u540e\u8fd8\u53ef\u4ee5\u53c2\u8003\u8fd9\u4e9b<a href=\"https:\/\/cn.hostease.com\/blog\/guides\/ttfb-hosting-optimization\/\">\u7f51\u7ad9\u6027\u80fd\u4f18\u5316\u65b9\u6cd5<\/a>\u505a\u5e94\u7528\u5c42\u7684\u8fdb\u4e00\u6b65\u63d0\u5347\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/cn.hostease.com\/blog\/wp-content\/uploads\/2026\/10\/cloud-server-mtu-network-layers.webp\" alt=\"\u5bb9\u5668\u4e0e\u96a7\u9053\u5206\u5c42 MTU \u7ed3\u6784\u56fe\uff1a\u7269\u7406\u94fe\u8def\u3001\u96a7\u9053\u3001\u5bb9\u5668\u4e09\u5c42\u9010\u5c42\u9012\u51cf\" loading=\"lazy\" \/><\/p>\n<h2>\u96a7\u9053\u573a\u666f\u7684 MTU \u8bbe\u7f6e\u4e0e\u9a8c\u8bc1<\/h2>\n<p>\u96a7\u9053\u573a\u666f\u7684\u5173\u952e\u662f\u8ba9\u96a7\u9053\u5185\u5c42\u8d1f\u8f7d\u52a0\u4e0a\u5c01\u88c5\u5934\u4e0d\u8d85\u8fc7\u7269\u7406\u94fe\u8def MTU\u3002\u5404\u5e38\u89c1\u534f\u8bae\u7684\u63a8\u8350\u914d\u7f6e\u503c\u5982\u4e0b\uff1a<\/p>\n<table>\n<thead>\n<tr>\n<th>\u96a7\u9053\u534f\u8bae<\/th>\n<th>\u5c01\u88c5\u5f00\u9500<\/th>\n<th>\u7269\u7406\u94fe\u8def 1500 \u65f6\u7684\u63a8\u8350 MTU<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>WireGuard<\/td>\n<td>60 \u5b57\u8282<\/td>\n<td>1420<\/td>\n<\/tr>\n<tr>\n<td>GRE<\/td>\n<td>24 \u5b57\u8282<\/td>\n<td>1476<\/td>\n<\/tr>\n<tr>\n<td>VXLAN<\/td>\n<td>50 \u5b57\u8282<\/td>\n<td>1450<\/td>\n<\/tr>\n<tr>\n<td>IPIP<\/td>\n<td>20 \u5b57\u8282<\/td>\n<td>1480<\/td>\n<\/tr>\n<tr>\n<td>OpenVPN (UDP\/TUN)<\/td>\n<td>28-58 \u5b57\u8282<\/td>\n<td>1420-1450<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u4ee5 WireGuard \u4e3a\u4f8b\uff0c\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u5199\u5165\uff1a<\/p>\n<pre><code class=\"language-ini\">[Interface]\nMTU = 1420\n<\/code><\/pre>\n<p>\u914d\u7f6e\u540e\u7528 <code>wg show<\/code> \u786e\u8ba4\u63a5\u53e3\u72b6\u6001\uff0c\u518d\u7528\u5927\u5305 ping \u9a8c\u8bc1\u96a7\u9053\u5bf9\u7aef\u3002\u5982\u679c\u96a7\u9053\u4e24\u7aef\u7684\u5185\u7f51\u8fd8\u8981\u518d\u5957\u4e00\u5c42\u5bb9\u5668\u7f51\u7edc\uff0c\u8981\u6309&#8221;\u9010\u5c42\u9012\u51cf&#8221;\u539f\u5219\uff1a\u7269\u7406 1500 \u2192 \u96a7\u9053 1420 \u2192 \u5bb9\u5668 1370\uff0c\u4efb\u4f55\u4e00\u5c42\u8d85\u51fa\u4e0a\u4e00\u5c42\u53ef\u7528\u7a7a\u95f4\u90fd\u4f1a\u590d\u73b0\u540c\u6837\u7684\u95ee\u9898\u3002<\/p>\n<p>\u8fc7\u6e21\u671f\u6709\u4e00\u79cd\u4fdd\u5b88\u505a\u6cd5\u503c\u5f97\u4e86\u89e3\uff1a\u628a\u4e24\u7aef MSS\uff08\u6700\u5927\u6bb5\u5927\u5c0f\uff09\u94b3\u5236\u5230\u6bd4 MTU \u63a8\u7b97\u503c\u66f4\u5c0f\u7684\u6570\u503c\uff0c\u8ba9 TCP\uff08\u4f20\u8f93\u63a7\u5236\u534f\u8bae\uff09\u4e3b\u52a8\u58f0\u660e\u8f83\u5c0f\u7684\u5206\u6bb5\uff0c\u7ed5\u8fc7\u8def\u5f84\u4e0a\u7684\u5206\u7247\uff1a<\/p>\n<pre><code class=\"language-bash\">iptables -t mangle -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu\n<\/code><\/pre>\n<p>\u8fd9\u662f\u6392\u969c\u671f\u7684\u4e34\u65f6\u624b\u6bb5\uff0c\u6cbb\u6807\u4e0d\u6cbb\u672c\u2014\u2014\u5b83\u53ea\u5bf9 TCP \u751f\u6548\uff0cUDP\uff08\u7528\u6237\u6570\u636e\u62a5\u534f\u8bae\uff09\u6d41\u91cf\u4e0d\u53d7\u5f71\u54cd\u3002\u5b9a\u4f4d\u5e76\u4fee\u6b63 MTU \u914d\u7f6e\u540e\uff0c\u5e94\u79fb\u9664\u8fd9\u6761\u89c4\u5219\uff0c\u907f\u514d\u53cc\u91cd\u8c03\u6574\u5e26\u6765\u7684\u6df7\u4e71\u3002<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/cn.hostease.com\/blog\/wp-content\/uploads\/2026\/10\/cloud-server-mtu-network-fix.webp\" alt=\"\u96a7\u9053\u4e24\u7aef MTU \u7edf\u4e00\u8c03\u6574\u540e\u62a5\u6587\u987a\u5229\u901a\u8fc7\u7684\u793a\u610f\" loading=\"lazy\" \/><\/p>\n<p>\u5728 Hostease \u7684<a href=\"https:\/\/cn.hostease.com\/vps\/\">\u4e91\u670d\u52a1\u5668<\/a>\u4e0a\uff0c\u5982\u679c\u9047\u5230\u8de8\u53ef\u7528\u533a\u7ec4\u7f51\u6216\u5bb9\u5668\u96c6\u7fa4\u7684\u7f51\u7edc\u5f02\u5e38\uff0c\u53ef\u4ee5\u5148\u6309\u672c\u6587\u65b9\u6cd5\u81ea\u67e5\u8def\u5f84 MTU\uff1b\u786e\u8ba4\u9700\u8981\u673a\u623f\u4fa7\u914d\u5408\u6392\u67e5\u65f6\uff0c\u63d0\u4ea4\u5de5\u5355\u8bf4\u660e&#8221;\u5927\u5305 ping \u5931\u8d25\u7684\u5177\u4f53\u8d1f\u8f7d\u503c\u548c\u76ee\u6807\u5730\u5740&#8221;\uff0c\u80fd\u8ba9\u652f\u6301\u56e2\u961f\u66f4\u5feb\u5b9a\u4f4d\u94fe\u8def\u73af\u8282\u3002<\/p>\n<h2>\u603b\u7ed3\u4e0e\u884c\u52a8\u5efa\u8bae<\/h2>\n<p>MTU \u95ee\u9898\u7684\u6392\u67e5\u53ef\u4ee5\u6536\u655b\u6210\u4e00\u4e2a\u56fa\u5b9a\u52a8\u4f5c\u5e8f\u5217\uff1a\u5148\u7528 <code>ping -M do -s &lt;\u8d1f\u8f7d&gt;<\/code> \u4e8c\u5206\u6d4b\u51fa\u8def\u5f84 MTU\uff0c\u518d\u7528 <code>ip link show<\/code> \u6838\u5bf9\u5404\u63a5\u53e3\u914d\u7f6e\uff0c\u7136\u540e\u6309\u5c01\u88c5\u5f00\u9500\u9010\u5c42\u4e0b\u8c03\u96a7\u9053\u548c\u5bb9\u5668\u7f51\u7edc\uff0c\u6700\u540e\u7528\u771f\u5b9e\u4e1a\u52a1\u6d41\u91cf\u9a8c\u8bc1\u3002<\/p>\n<p>\u7ed9\u51fa\u4e09\u6761\u5177\u4f53\u5efa\u8bae\uff1a<\/p>\n<ul>\n<li>\u65b0\u5efa\u5bb9\u5668\u96c6\u7fa4\u6216\u96a7\u9053\u524d\uff0c\u5148\u6309\u5c01\u88c5\u534f\u8bae\u9884\u7559\u5b57\u8282\u5e76\u7edf\u4e00\u89c4\u5212\u5404\u5c42 MTU\uff0c\u6bd4\u4e8b\u540e\u6392\u969c\u6210\u672c\u4f4e\u5f97\u591a<\/li>\n<li>\u4e91\u5e73\u53f0\u5b89\u5168\u7ec4\u653e\u884c ICMP type 3 code 4\uff0c\u4fdd\u8bc1 PMTUD \u673a\u5236\u53ef\u7528\uff0c\u8fd9\u662f\u5f88\u591a&#8221;\u5076\u53d1\u8d85\u65f6&#8221;\u7684\u9690\u85cf\u6839\u6e90<\/li>\n<li>\u628a <code>ping -M do -s 1472 \u6d4b\u8bd5\u5730\u5740<\/code> \u52a0\u8fdb\u65e5\u5e38\u5de1\u68c0\u811a\u672c\uff0c\u8def\u5f84 MTU \u7a81\u7136\u53d8\u5c0f\u5f80\u5f80\u6bd4\u4e1a\u52a1\u62a5\u9519\u66f4\u65e9\u66b4\u9732\u94fe\u8def\u53d8\u66f4<\/li>\n<\/ul>\n<p>\u5982\u679c\u4f60\u9700\u8981\u8fdb\u4e00\u6b65\u6838\u5bf9\u5177\u4f53\u7684\u5c01\u88c5\u5f00\u9500\u6570\u503c\uff0c\u5efa\u8bae\u4ee5\u6240\u7528\u534f\u8bae\u7684\u5b98\u65b9\u6587\u6863\u4e3a\u51c6\uff0c\u4e0d\u540c\u7248\u672c\u5b9e\u73b0\u53ef\u80fd\u6709\u51e0\u5b57\u8282\u7684\u5dee\u5f02\uff0c\u4f46\u6392\u67e5\u601d\u8def\u548c\u672c\u6587\u5b8c\u5168\u4e00\u81f4\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e91\u670d\u52a1\u5668\u4e0a\u5bb9\u5668\u7f51\u7edc\u548c VPN \u96a7\u9053\u573a\u666f\u7684 MTU \u8c03\u6574\u65b9\u6cd5\uff1a\u5982\u4f55\u5b9a\u4f4d\u5206\u7247\u4e22\u5305\u3001\u8ba1\u7b97\u6b63\u786e\u7684 MTU \u503c\uff0c\u5e76\u7528\u547d\u4ee4\u9010\u5c42\u9a8c\u8bc1\u7f51\u7edc\u914d\u7f6e\u3002<\/p>\n","protected":false},"author":2,"featured_media":33432,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3822],"tags":[5182,111,4968,4559,5183],"class_list":["post-33436","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guides","tag-mtu","tag-111","tag-4968","tag-4559","tag-5183"],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/cn.hostease.com\/blog\/wp-content\/uploads\/2026\/10\/cloud-server-mtu-network-cover.webp","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/posts\/33436","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/comments?post=33436"}],"version-history":[{"count":1,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/posts\/33436\/revisions"}],"predecessor-version":[{"id":33445,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/posts\/33436\/revisions\/33445"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/media\/33432"}],"wp:attachment":[{"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/media?parent=33436"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/categories?post=33436"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cn.hostease.com\/blog\/wp-json\/wp\/v2\/tags?post=33436"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}