1 、日志简介 nginx 日志主要有两种:访问日志和 错误 日志。访问日志主要记录客户端访问 nginx 的每一个请求,格式可以自定义; 错误 日志主要记录客户端访问 nginx 出错时的日志,格式不支持自定义。两种日志都可以选择性关闭。 通过访问日志,你可以得到
1、日志简介
nginx日志主要有两种:访问日志和错误日志。访问日志主要记录客户端访问nginx的每一个请求,格式可以自定义;错误日志主要记录客户端访问nginx出错时的日志,格式不支持自定义。两种日志都可以选择性关闭。
通过访问日志,你可以得到用户地域来源、跳转来源、使用终端、某个URL访问量等相关信息;通过错误日志,你可以得到系统某个服务或server的性能瓶颈等。因此,将日志好好利用,你可以得到很多有价值的信息。
[Access.log]
log_format main '$remote_addr
'$status $upstream_status
'"$http_user_agent"
'$request_time
变量名称
变量描述
举例说明
$remote_addr
客户端地址
113.140.15.90
$remote_user
客户端用户名称
-
$time_local
访问时间和时区
18/Jul/2012:17:00:01
$request
请求的URI和HTTP协议
"GET
$http_host
请求地址,即浏览器中你输入的地址(IP或域名)
img.alipay.com
10.253.70.103
$status
HTTP请求状态
200
$upstream_status
upstream状态
200
$body_bytes_sent
发送给客户端文件内容大小
547
$http_referer
跳转来源
"https://cashier.alipay.com.../"
$http_user_agent
用户终端代理
"Mozilla/4.0 (compatible; MSIE
$ssl_protocol
SSL协议版本
TLSv1
$ssl_cipher
交换数据中的算法
RC4-SHA
$upstream_addr
后台upstream的地址,即真正提供服务的主机地址
10.228.35.247:80
$request_time
整个请求的总时间
0.205
$upstream_response_time
请求过程中,upstream响应时间
0.002
线上实例:
116.9.137.90 -
2、访问日志
$remote_user [$time_local] "$request" $http_host '
$body_bytes_sent "$http_referer" '
$ssl_protocol $ssl_cipher $upstream_addr '
$upstream_response_time';
+0800
/pa/img/home/logo-alipay-t.png HTTP/1.1"
8.0; Windows NT 5.1; Trident/4.0; SV1; GTB7.0;
.NET4.0C;
[02/Aug/2012:14:47:12 +0800] "GET /images/XX/20100324752729.png HTTP/1.1"img.alipay.com 200 200 2038 https://cashier.alipay.com/XX/PaymentResult.htm?payNo=XX&outBizNo=2012XX "Mozilla/4.0
(compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727;
.NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Tablet PC 2.0;
360SE)" TLSv1 AES128-SHA 10.228.21.237:80 0.198 0.001
线下测试($http_referer):
10.14.21.197 - -
[14/Aug/2012:17:28:22 +0800] "GET
/spanner/watch/v1?--db=ztg-1&--mode=compare&--index=status&--option=&--cluster=whole&-F=2012%2F8%2F12-00%3A00%3A00&-T=%2B2880&-i=1&-n=0&_=1344936501292
HTTP/1.1" 200 94193 "http://spanner.alipay.net/optionFrame/history.html"
"Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.1 (KHTML, like Gecko)
Chrome/21.0.1180.60 Safari/537.1"
备注:$http_referer和重定向有关。
线下测试($http_host):
备注:$http_host的值和你在浏览器里输入的值有关。
3、错误日志
错误信息 |
错误说明 |
"upstream prematurely(过早的) closed connection" |
请求uri的时候出现的异常,是由于upstream还未返回应答给用户时用户断掉连接造成的,对系统没有影响,可以忽略 |
"recv() failed (104: Connection reset by |
(1)服务器的并发连接数超过了其承载量,服务器会将其中一些连接Down掉; (2)客户关掉了浏览器,而服务器还在给客户端发送数据; (3)浏览器端按了Stop |
"(111: Connection refused) while connecting to |
用户在连接时,若遇到后端upstream挂掉或者不通,会收到该错误 |
"(111: Connection refused) while reading response header |
用户在连接成功后读取数据时,若遇到后端upstream挂掉或者不通,会收到该错误 |
"(111: Connection refused) while sending request to |
Nginx和upstream连接成功后发送数据时,若遇到后端upstream挂掉或者不通,会收到该错误 |
"(110: Connection timed out) while connecting to |
nginx连接后面的upstream时超时 |
"(110: Connection timed out) while reading |
nginx读取来自upstream的响应时超时
|
"(110: Connection timed out) while reading response |
nginx读取来自upstream的响应头时超时 |
"(110: Connection timed out) while reading |
nginx读取来自upstream的响应时超时 |
"(104: Connection reset by peer) while connecting to |
upstream发送了RST,将连接重置 |
"upstream sent invalid header while reading response |
upstream发送的响应头无效 |
"upstream sent no valid HTTP/1.0 header while reading |
upstream发送的响应头无效 |
"client intended to send too large |
用于设置允许接受的客户端请求内容的最大值,默认值是1M,client发送的body超过了设置值 |
"reopening logs" |
用户发送kill -USR1命令 |
"gracefully shutting down", |
用户发送kill -WINCH命令 |
"no servers are inside upstream" |
upstream下未配置server |
"no live upstreams while connecting to |
upstream下的server全都挂了 |
"SSL_do_handshake() failed" |
SSL握手失败 |
"SSL_write() failed (SSL:) while sending to |
|
"(13: Permission denied) while reading |
|
"(98: Address already in use) while connecting to |
|
"(99: Cannot assign requested address) while connecting |
|
"ngx_slab_alloc() failed: no memory in SSL session shared |
ssl_session_cache大小不够等原因造成 |
"could not add new SSL session to the session cache while |
ssl_session_cache大小不够等原因造成 |
"send() failed (111: Connection |
|

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