Hi,

In a local LAN network I observe an insane amount OF ARP requests and
replies. I see ARP requests coming from Suse 10.1 Linux workstations,
sometimes like a real flood, some hundred in a second. Examle of a
network sniff on a host, filtered with it's own MAC address:

tcpdump -n arp and ether host 00:18:8B:2B:C2:A5
....
16:56:49.209922 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210045 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210083 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210118 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210155 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210200 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210234 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210262 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210305 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210337 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210372 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210426 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210447 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210481 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210517 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210587 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210604 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210663 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210670 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210706 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210736 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210773 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210819 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210847 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210890 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210932 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.210953 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211027 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211039 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211063 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211100 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211139 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211171 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211207 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211245 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211279 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211316 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211352 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211392 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211425 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211462 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211498 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211534 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211571 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211643 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211650 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211679 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211732 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211753 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211790 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211827 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211875 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211898 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211937 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.211978 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212008 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212045 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212082 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212131 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212152 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212189 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212226 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212261 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212298 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212334 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212373 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212406 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212443 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212480 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212516 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212553 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212588 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212627 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212661 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212707 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212734 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212772 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212807 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212861 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212879 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212970 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212983 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.212994 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213025 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213061 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213106 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213141 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213207 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213216 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213244 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213280 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213323 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213357 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213389 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213440 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213462 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213499 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213543 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213578 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213608 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213646 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213691 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213717 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213753 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213793 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213833 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213862 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213900 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213941 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.213973 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214006 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214047 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214085 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214116 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214153 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214189 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214226 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214262 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214301 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214333 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214370 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214407 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214443 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214480 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214516 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214555 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214588 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214626 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214662 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214697 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214733 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214779 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214806 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214841 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214879 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214915 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214952 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.214988 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215024 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215060 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215096 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215134 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215169 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215205 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215242 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215281 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215314 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215351 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215396 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215424 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215460 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215497 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215535 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215568 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215606 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215642 arp who-has gilera.example.com tell
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16:56:49.215678 arp who-has gilera.example.com tell
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16:56:49.215715 arp who-has gilera.example.com tell
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16:56:49.215763 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215786 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215823 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.215860 arp who-has gilera.example.com tell
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16:56:49.215897 arp who-has gilera.example.com tell
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16:56:49.215933 arp who-has gilera.example.com tell
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16:56:49.216005 arp who-has gilera.example.com tell
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16:56:49.218047 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.218080 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:49.218116 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:50.209935 arp who-has gilera.example.com tell
adnwsrs25.zh.example.com
16:56:50.210029 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210043 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210048 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210051 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210055 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210059 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210063 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210066 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210070 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210081 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210085 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210089 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210093 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210096 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)
16:56:50.210107 arp reply gilera.example.com is-at 08:00:20:fe:ca:66
(oui Unknown)

The one who replies the ARP requests is our backbone layer 3 switch
from Extreme Networks. Is this behaviour normal? I would expect that
one ARP broadcast request and one reply should be enough. Why are
there so many?

Thanks in advance for help.

Best regards,
Bernd