Is there any way to adjust the amount of time that dynamic ARP entries remain in the ARP table on RouterOS? I can’t seem to find any such setting if it exists…please tell me that I’m just blind. 
Thanks,
– Nathan
Uhhh…I’ll take that lack of response as a “no”…?
– Nathan
Hi Nathan,
yes, this thing is “on” 
…
I’m not aware of a possibility to change the timeout of dynamic ARP entries.
Hello!
Are it possible now?
After RouterOS was positioned as CoreRouter.
I see timeout = 1 minute on my border router, with Internet Exchange it is too little time.
That does not allow to use the blackhole service.
How does the blackhole route relate to ARP cache timeout? Please clarify why you would need such feature?
Hello, Normis.
This feature needs in many cases.
Our network ARP timeout standard is 4minutes (1 minute less, that CAM timeout). I want to adjust it on RouterOS too.
Low value makes high level of broadcast flood.
This tunable on most of network devices.
How does the blackhole route relate to ARP cache timeout?
MSK-IX service ‘Blackhole for attack protection’ sends ARP announces every 5 minutes. If timeout is less - ARP to become obsolete.
It is only one case of many.
Also for network engineer would be very convenient command for cleaning ARP table without using scripts or complex commands.