DNS的日志记录参数详解及示例

在"man named.conf"中能找到关于日志的配置选项：

    logging {
          category string { string; ... };
          channel string {
               buffered boolean;
               file quoted_string [ versions ( "unlimited" | integer )
                   ] [ size size ];
               null;
               print-category boolean;
               print-severity boolean;
               print-time boolean;
               severity log_severity;
               stderr;
               syslog [ syslog_facility ];
          };
     };

category(类别)：选择需要记录的日志类别主要有以下参数：
default         #匹配未归类的消息类型。
general        #包括所有未明确的bind消息
client        #客户端的请求消息
config        #配置文件相关消息
database        #存储数据和缓存记录
dnssec        #域名签名日志
lame-servers        #未授权或者非法
network        #网络错误
notify        #异步区的更新消息
queries        #查询日志
query-errors       #查询不到
resolver        #名字解析，包括递归日志
security        #安全日志
update        #部分更新日志
cname        #别名解析
xfer-in        #从远程域名服务器到本地服务器的数据消息
xfer-out        #从本地到远程域名服务器的数据消息

示例：
category config { default_syslog; default_debug; default_log; };
#记录config相关消息，分别记录到括号里的三个位置

channel(通道)：规定category括号中的记录日志位置及消息等级
示例：
channel default_debug {
print-time yes;
print-category yes;
print-severity yes;
file “named.run”;
severity dynamic;

print-category：记录消息时是否记录日志类型
severity：记录消息的等级(严重性从上往下递减)：
critical
error
warning
notice
info
debug [ level ]
dynamic
定义了某个级别后，会记录比该级别更严重的日志。

print-time：是否记录消息的时间
print-severity：记录消息时是否写入消息级别
print-category：记录消息时是否写入消息类型

配置示例：
logging {
            category network { default_syslog; default_debug; default_log; };
            category default { default_log; };
            category config { default_log; };
            channel default_log {
               file “/var/named/log/default.log” versions 3 size 20m;
               print-time yes;
               print-category yes;
               print-severity yes;
               severity info;
               };
#上面三个类型的日志全部记录到/var/named/log/default.log文件中，version设置为3将会保存3份日志，上限存储20M，依次版本循环记录日志。

            category cname { auth_servers_log; };
            channel auth_servers_log {
               file “/var/named/log/auth_servers.log” versions 5 size 20m;
               print-time yes;
               print-category yes;
               print-severity yes;
               severity info;
               };

            category client{ client_security_log;};
            category security { client_security_log;};
            channel client_security_log {
               file “/var/named/log/client_security.log” versions 3 size 20m;
               print-time yes;
               print-category yes;
               print-severity yes;
               severity info;
               };

            category queries { queries_log; };
            channel queries_log {
               file “/var/named/log/queries.log” versions 10 size 20m;
               print-time yes;
               print-category yes;
               print-severity yes;
               severity info;
               };

            category query-errors {query-errors_log; };
            channel query-errors_log {
               file “/var/named/log/query-errors” versions 5 size 20m;
               print-time yes;
               print-category yes;
               print-severity yes;
               severity dynamic;
             };
  };