Shell Programming and Scripting

Hello all,

Here is the explanation of my problem:
I have a cronjob that connects to a NAS to do backups from my laptop to this NAS device.
The script that I wrote does check if there is a host (the NAS) responding on 192.168.1.10 and tries to connect to it with the following command:

Code:

mount -v -t cifs -o user=fred_fedora%passwd //192.168.1.10/share /media/Big

And well, it works perfectly when I am at home, but:
Problem:
When I am connected on a network at some clients, I realized that it is also trying to connect to some computer on 192.168.1.10 if there is a host responding at this address on the network...

Question:
How would you check the hostname of the host on 192.168.1.10 before trying to connect to it?
What is the best way to check that you are in touch with the host you know and trust before trying to connect to it?

Many thanks for your help and keep up the good work!

Since you only want the home machine, check the mac address? After all, you cannot be sure it is something you can log in to but it has to be something you can ARP. Of course, you need a tool that can do an ARP on the local network.

Alternatively, since you can log into your own host, just "ssh -n nas_host uname -n" with PPK authentication.

Many thanks for your reply!

Indeed I thought about ssh on to the NAS with a private key installed but there is no ssh server on this old NAS...
For the Address Resolution Protocol (arp -ev 192.168.10) works great to give me the MAC address of my device.
Therefore it seems I have the right tools to arp!!
Good!! But could you please be a bit more specific on the kind of tool I have to ARP on my network in order to check the MAC address associated with the ip?
On other network how to check if I have such a tool?
I guess I just try the command arp..? But How to get this arp tool if I do not have it?
Please any links to more resource about this is more than appreciated.

Thanks again for your help, that is great advice!

It occurs to me that if you just ping the local collision domain Ethernet host, the mac will be in your host's ARP cache, if you can find where it is or list it.

Google time: How to display/clear ARP cache?

How to display ARP cache in Linux ?
There are two commands to display ARP cache.
Command 1 : ip neighbor show

[root@avas-2 ~]# ip neighbor show

Command 2 : arp

[root@avas-2 ~]# arp