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Netkiller Cisco IOS 手札
2009-12-12
版权 ? 2009, 2010, 2011 Neo Chan
版权声明
转载请与作者联系，转载时请务必标明文章原始出处和作者信息及本声明。
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文档出处:?http://netkiller.sourceforge.net/?|?http://netkiller.github.com
文档最近一次更新于?Tue Nov 29 11:45:42 UTC 2011
下面是我多年积累下来的经验总结，整理成文档供大家参考:
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| Netkiller Architect 手札 | Netkiller Linux 手札 | Netkiller Developer 手札 | Netkiller Database 手札 |
| Netkiller Debian 手札 | Netkiller CentOS 手札 | Netkiller FreeBSD 手札 | Netkiller Shell 手札 |
| Netkiller Web 手札 | Netkiller Monitoring 手札 | Netkiller Storage 手札 | Netkiller Mail System 手札 |
| Netkiller MySQL 手札 | Netkiller LDAP 手札 | Netkiller Security 手札 | Netkiller Version 手札 |
| Netkiller Intranet 手札 | Netkiller Cisco IOS 手札 | Netkiller Writer 手札 | Netkiller Studio Linux 手札 |
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当你空降到一家新公司，一般情况下都是，工作一团乱麻，前任迫不及待的等待工作交接或者工作转移，
等着你去救火，如果工作井然有序，公司也不能去招聘新人。
所有当你看到一团乱麻的网络与服务器，束手无策，你想重新整理，又不能影响现有业务。
怎样快速寻找交换机端口对应的服务器。我使用过很多方法（不能中断网络，所有不能使用寻线设备），开始show arp
show mac地址表，寻找对应关系，比较麻烦。
后来想到CDP协议，采用tcpdump 抓包，可以快速看到服务器插在那个交换机端口上。
$ sudo tcpdump -nn -v -i eth0 -s 1500 -c 1 'ether[20:2] == 0x2000'[sudo] password for neo:tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 1500 bytes13:51:31.825893 CDPv2, ttl: 180s, checksum: 692 (unverified), length 375 Device-ID (0x01), length: 7 bytes: '4A3750G' Version String (0x05), length: 182 bytes: Cisco IOS Software, C3750 Software (C3750-IPBASE-M), Version 12.2(35)SE5, RELEASE SOFTWARE (fc1) Copyright (c) 1986-2007 by Cisco Systems, Inc. Compiled Thu 19-Jul-07 19:15 by nachen Platform (0x06), length: 23 bytes: 'cisco WS-C3750G-24TS-1U' Address (0x02), length: 13 bytes: IPv4 (1) 193.168.0.254 Port-ID (0x03), length: 21 bytes: 'GigabitEthernet1/0/15' Capability (0x04), length: 4 bytes: (0x00000029): Router, L2 Switch, IGMP snooping Protocol-Hello option (0x08), length: 32 bytes: VTP Management Domain (0x09), length: 3 bytes: 'xiu' Native VLAN ID (0x0a), length: 2 bytes: 11 Duplex (0x0b), length: 1 byte: full AVVID trust bitmap (0x12), length: 1 byte: 0x00 AVVID untrusted ports CoS (0x13), length: 1 byte: 0x00 Management Addresses (0x16), length: 13 bytes: IPv4 (1) 193.168.0.254 unknown field type (0x1a), length: 12 bytes: 0x0000: 0000 0001 0000 0000 ffff ffff1 packets captured1 packets received by filter0 packets dropped by kernel
$ sudo tcpdump -nn -v -i eth0 -s 1500 -c 1 'ether[20:2] == 0x2000' | grep GigabitEthernet[sudo] password for neo:tcpdump: listening on eth0, link-type EN10MB (Ethernet), capture size 1500 bytes Port-ID (0x03), length: 21 bytes: 'GigabitEthernet1/0/15'1 packets captured1 packets received by filter0 packets dropped by kernel
运行命令后显示
Port-ID (0x03), length: 21 bytes: 'GigabitEthernet1/0/15'?这个就是交换机对应的端口
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在每个服务器上创建一个脚本port.sh
tcpdump -nn -v -i eth0 -s 1500 -c 1 'ether[20:2] == 0x2000' | grep GigabitEthernet
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然后批量执行
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for ip in {23..32} {49,50,53,54} {81..92} {121..127}; do rsh [email protected]$ip port.sh & done &
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