Hello Netview-folks around the planet, Hello Leslie
recently there was a discussion around ARP-cache-tuning on this forum.
I would like to say thank You to Leslie Clark for his excellent tuning tip.
We suffered from loss of ARP-Cache-entries which caused an ARP-broadcast
in front of every Ping that was sent out by Netview-netmon-Ping or
Optivities "Superping"
Our local network consists of 250 devices to Ping every 10 minutes
(Output from no -a command)
arptab_bsiz = 7 arptab_nb = 25 arpqsize = 1 arpt_killc = 20
But with these values only a maximum of around 175 entries where found with
the
command arp-a in the ARP-Cache. (command arp -a|wc)
And despite the Kill-time of 20 minutes we lost ARP-entries already after
3-5 minutes !!
According to Leslies' advice I changed the values by adding the following
statements to
the beginning of file rc.net and rebooted the machine
#!/bin/ksh
/usr/sbin/no -o arptab_bsiz=40
/usr/sbin/no -o arptab_nb=140
...rest of rc.net....
With these values over 400 entries are now possible in the ARP-cache.
The second effect is, we see much less false alarms on our Netview-machine!
We found that besides Netview, also Optivity is pinging around using a
completly
different timing sheme. (Every 150seconds)
This caused additional atttempts to add new ARP-entries into the
underdimensioned
ARP-Cache.
By the way, does anybody know how to change the Polling-interval of
Optivity ?
```
(o o)
------------------oOO-(_)-OOo------------------
Winfried Gehrig mailto:Winfried.Gehrig@skf.com
SKF GmbH FON ++49(0)9721 56 3077
Gunnar Wester Str. 12 Virtual FAX ++49(0)9721 5663266
97421 Schweinfurt
(Germany)
Our bearings turn the planet
http://www.skf.com
-----------------------------------------------
|