mongodb监控工具mongosniff
介绍
mongosniff提供了对数据库实时活动的低级别操作跟踪和嗅探视图。可以将mongosniff认为是专为MongoDB定制的，类似于tcpdump用于TCP/IP网络流量分析。mongosniff常用于驱动开发。
注意：mongosniff需要libpcap，并且只对类Unix系统可用。
相对于mongosniff，Wireshark，一个流行的网络嗅探工具，可用于侦测和解析MongoDB线协议。
用法
下面的命令连接到运行在localhost的27017和27018上的mongod或mongos：
mongosniff --source NET lo 27017 27018
下面的命令只记录运行在localhost的27018上的mongod或mongos的无效的BSON对象，用于驱动开发和问题跟踪：
mongosniff --objcheck --source NET lo 27018
实践
[root@test ~]# mongosniff --help
mongosniff: error while loading shared libraries: libpcap.so.0.9: cannot open shared object file: No such file or directory
[root@test ~]# which mongosniff
/usr/bin/mongosniff
[root@test ~]# ldd /usr/bin/mongosniff
linux-vdso.so.1 => (0x00007fffe2d7a000)
libpthread.so.0 => /lib64/libpthread.so.0 (0x0000003558e00000)
librt.so.1 => /lib64/librt.so.1 (0x0000003559200000)
libpcap.so.0.9 => not found
libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x0000003559e00000)
libm.so.6 => /lib64/libm.so.6 (0x0000003559600000)
libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x000000355a600000)
libc.so.6 => /lib64/libc.so.6 (0x0000003558a00000)
/lib64/ld-linux-x86-64.so.2 (0x0000003558200000)
可以看出libpcap.so.0.9 => not found并没有找到。
[root@test ~]# cd /usr/lib64
[root@test lib64]# ls -al | grep libpcap
lrwxrwxrwx. 1 root root 16 Feb 26 17:28 libpcap.so.1 -> libpcap.so.1.4.0
-rwxr-xr-x 1 root root 260880 Nov 22 2013 libpcap.so.1.4.0
添加软连接。
[root@test lib64]# ln -s /usr/lib64/libpcap.so.1.4.0 /usr/lib64/libpcap.so.0.9
再次查看帮助。
[root@test lib64]# mongosniff --help
Usage: mongosniff [--help] [--forward host:port] [--source (NET <interface> | (FILE | DIAGLOG) <filename>)] [<port0> <port1> ... ]
--forward Forward all parsed request messages to mongod instance at
specified host:port
--source Source of traffic to sniff, either a network interface or a
file containing previously captured packets in pcap format,
or a file containing output from mongod's --diaglog option.
If no source is specified, mongosniff will attempt to sniff
from one of the machine's network interfaces.
--objcheck Log hex representation of invalid BSON objects and nothing
else. Spurious messages about invalid objects may result
when there are dropped tcp packets.
<port0>... These parameters are used to filter sniffing. By default,
only port 27017 is sniffed.
--help Print this help message.抓包：
[root@test lib64]# /usr/bin/mongosniff --source NET bond0 > /var/log/currentOp/sniff.log下面是sniff.log中的部分内容：
10.10.0.1:55553 -->> 10.10.0.2:27017 MyTest.Pro 1042 bytes id:41d99 269721
query: { $query: { id: { $in: [ 380, 383 ] }, Availability.Status: { $lt: 5 }, $or: [ { id: { $lt: 331 } }, { id: { $gt: 200, $lt: 400 } }, { id: { $gt: 600, $lt: 800 } } ] }, $orderby: { Availability.Status: 1 } } ntoreturn: 0 ntoskip: 0 hasfields SlaveOk
