野口です。
社内にいる発信源はわかるが MAC アドレスが不明な端末を特定したいとき。
同じ L2 セグメントにいる必要があるので注意。
じゃないとルータの IP アドレスになる。
MACアドレスフィルタリングかかってて無線環境でプライバシーセパレータ有効になってて端末同士の通信が禁止されているときに便利。
RT# show arp
Count: 60
Interface IP address MAC address TTL(second)
LAN2 10.123.56.11 f0:ff:de:a6:5b:b1 684
LAN1/1 10.123.73.11 f0:ff:c8:ab:0b:f1 828
LAN1/1 10.123.73.12 f4:ff:c6:ab:9b:f1 423
LAN1/1 10.123.73.14 f0:ff:7f:ae:0b:31 17
LAN1/1 10.123.73.16 f0:ff:32:a9:0b:f1 507
LAN1/1 10.123.73.17 f4:ff:c6:ab:9b:81 1151
LAN1/1 10.123.73.18 f8:ff:8a:af:2b:81 1175
LAN1/1 10.123.73.22 f4:ff:30:a5:ab:b1 457
LAN1/1 10.123.73.23 fc:ff:d5:ad:bb:11 477
LAN1/1 10.123.73.24 f4:ff:e6:a8:1b:61 581
LAN1/1 10.123.73.25 f0:ff:29:aa:6b:d1 37
LAN1/1 10.123.73.26 f0:ff:fe:a8:ab:b1 1089
LAN1/1 10.123.73.27 f8:ff:7f:af:1b:f1 944
LAN1/1 10.123.73.28 f0:ff:d5:a1:fb:21 625
LAN1/1 10.123.73.30 f0:ff:34:a6:0b:61 1174
LAN1/1 10.123.73.31 f8:ff:ed:ae:db:11 702
LAN1/1 10.123.73.34 f8:ff:43:a8:eb:d1 453
LAN1/1 10.123.73.36 f8:ff:3c:a4:fb:91 1165
LAN1/1 10.123.73.38 f0:ff:d5:a3:2b:51 600
LAN1/1 10.123.73.39 fc:ff:75:af:3b:c1 940
(snip)
RT# show arp | grep 192.168.123.123
Searching ...
LAN1/5 192.168.123.123 ff:11:22:33:44:30 1049
犯人はお前だ!
投稿者紹介
-
* Bio: Software Engineer, Network and Server Engineer
* Certification:
IPA: FE, AP, Network Specialist
Cisco: CCNA R&S, CCNP R&S
LPI: LPIC Level1, Level2, LPIC-3 Specialty LPI-304 Virtualization &High Availability