cancel
Showing results for 
Search instead for 
Did you mean: 

arp cache query

SOLVED
Go to solution
Becke
Super Advisor

arp cache query


Hi All

Can someone explain exactly how arp cache works.

Basically I'm trying to figure out the which gateway to add for ip address (e.g 10.2.80.9)

i have pinged the above ip obviously there is no static route in the server to get to that ip hence it fails, i have then run
arp -an|head, Not exactly sure how it works from here and what we need to look at, usually it say something "incomplete entry" etc ?

Thanks in advance
4 REPLIES
TTr
Honored Contributor
Solution

Re: arp cache query

What are you trying to do, set up the default gateway for this server or set up a custom rout e for a specific ip?
rick jones
Honored Contributor

Re: arp cache query

I think you may be confusing routing with IP address to MAC address translation.

Which gateway to add for a given IP depends on which gateways on the locally connected subnets know how to get to that IP. Once determined, that would involve route(1m) commands to manipulate the routing table, and perhaps sam or vi to edit the /etc/rc.config.d/netconf file.

None of that involves ARP. ARP is for mapping (perceived to be) local IP addresses to MAC (Ethernet) addresses.
there is no rest for the wicked yet the virtuous have no pillows
Becke
Super Advisor

Re: arp cache query


Thanks for the response, It's not default gateway, I'm trying to work out the static route to be added on the local unix box so it can communicate to the destination ip ie 10.x.x.x...

fw is allowing everything.

what i have done in one of the other server to work this, I have pinged the destination ip in question and then did arp -an...that showed me an incomplete route which I have used to determine what static route can be added on the local hos so it knows how to communicate with the target ip...
rick jones
Honored Contributor

Re: arp cache query

If you have previously been able to ping the remote destination, that implies there was already *some* route on the system - perhaps the default route. So, why then add another route?
there is no rest for the wicked yet the virtuous have no pillows