Finding IPs on an Intranet

[OccamsRazor]

Setting up a wired Intranet (connected via an 8-port hub) and I will have 1 Windows based machine and 2 Linux based CPUs.

Using the Windows machine, how can I find the IP addresses for the Linux machines? I want to do speedy file transfers between the Linux machines via an interface from the Windows machine but, I will need to know the IPs in order to speak to the Linux boxes before I can transfer files. I am guessing that I will need to open a CMD line on the Windows machine but, how can I get the IPs? Typically, I do the file transfers over WiFi but, it is SLOWWWW!!! Thinking having them all wired via a hub will speed things up.

Thanks!

 

[Kyle]

The easiest would be to log onto your router and look up the DHCP clients listed.

 

[OccamsRazor]

The easiest would be to log onto your router and look up the DHCP clients listed.

Not a router. This would be an 8-port workgroup hub.

 

[Kyle]

Not a router. This would be an 8-port workgroup hub.

So the 8-port is not plugged into an internet connection at all?

If not, and you are working on a dual homed windows system, arp -a.



Displays and modifies the IP-to-Physical address translation tables used by
address resolution protocol (ARP).

ARP -s inet_addr eth_addr [if_addr]
ARP -d inet_addr [if_addr]
ARP -a [inet_addr] [-N if_addr] [-v]

-a Displays current ARP entries by interrogating the current
protocol data. If inet_addr is specified, the IP and Physical
addresses for only the specified computer are displayed. If
more than one network interface uses ARP, entries for each ARP
table are displayed.
-g Same as -a.
-v Displays current ARP entries in verbose mode. All invalid
entries and entries on the loop-back interface will be shown.
inet_addr Specifies an internet address.
-N if_addr Displays the ARP entries for the network interface specified
by if_addr.
-d Deletes the host specified by inet_addr. inet_addr may be
wildcarded with * to delete all hosts.
-s Adds the host and associates the Internet address inet_addr
with the Physical address eth_addr. The Physical address is
given as 6 hexadecimal bytes separated by hyphens. The entry
is permanent.
eth_addr Specifies a physical address.
if_addr If present, this specifies the Internet address of the
interface whose address translation table should be modified.
If not present, the first applicable interface will be used.
Example:

arp -s 157.55.85.212 00-aa-00-62-c6-09 .... Adds a static entry.
arp -a

 

[black dog]

So the 8-port is not plugged into an internet connection at all?

If not, and you are working on a dual homed windows system, arp -a.



Displays and modifies the IP-to-Physical address translation tables used by
address resolution protocol (ARP).

ARP -s inet_addr eth_addr [if_addr]
ARP -d inet_addr [if_addr]
ARP -a [inet_addr] [-N if_addr] [-v]
Alt-Binaries-Newsgroups/bestiality
-a Displays current ARP entries by interrogating the current
protocol data. If inet_addr is specified, the IP and Physical
addresses for only the specified computer are displayed. If
more than one network interface uses ARP, entries for each ARP
table are displayed.
-g Same as -a.
-v Displays current ARP entries in verbose mode. All invalid
entries and entries on the loop-back interface will be shown.
inet_addr Specifies an internet address.
-N if_addr Displays the ARP entries for the network interface specified
by if_addr.
-d Deletes the host specified by inet_addr. inet_addr may be
wildcarded with * to delete all hosts.
-s Adds the host and associates the Internet address inet_addr
with the Physical address eth_addr. The Physical address is
given as 6 hexadecimal bytes separated by hyphens. The entry
is permanent.
eth_addr Specifies a physical address.
if_addr If present, this specifies the Internet address of the
interface whose address translation table should be modified.
If not present, the first applicable interface will be used.
Example:

FIFY

 

[OccamsRazor]

So the 8-port is not plugged into an internet connection at all?

Not at all. Will be as follows:

Linux CPU 1 -----------------------> 8-port hub <-------------------- Linux CPU 2
Windows CPU ---------------------------^

 

[OccamsRazor]

I want to use the Windows CPU as the interface so I can log into the 2 Linux CPUs over the intrAnet and then transfer files from Linux CPU 1 to Linux CPU 2.

FYI... the hub is a Linksys 8-port Workgroup Hub Model EFAH08W

 

[Kyle]

Then use ARP from the windows machine, but another question is if you built these two Linux systems, did you not assign them an IP address at configuration?

 

[HemiHauler]

Ping the broadcast address for your subnet. Every host should answer unless ICMP is blocked

 

[OccamsRazor]

Then use ARP from the windows machine, but another question is if you built these two Linux systems, did you not assign them an IP address at configuration?

Both of the Linux boxes are Raspberry Pis. I believe (when connected to a router and over Wifi or wired) they are assigned IPs by the system. In the scenario that I am speaking of, there is no IP assignment by a router.

 

[Ken King]

1. Open a terminal window to get to the command line.
2. For Linux issue the command ifconfig and press Return. (for Windows it would be ipconfig)
3. Enter the command arp -a to get more information.

 

[OccamsRazor]

1. Open a terminal window to get to the command line.
2. For Linux issue the command ifconfig and press Return. (for Windows it would be ipconfig)
3. Enter the command arp -a to get more information.

Wouldn't running ipconfig (or ifconfig on Linux) only give me the IP info from THAT machine? I will want to see the Linux machine(s) IP info from the Windows machine.

Sorry if this sounds dense. Trying to learn.

 

[Sneakers]

Wouldn't running ipconfig (or ifconfig on Linux) only give me the IP info from THAT machine?

Yes.

Why not turn off DHCP and manually enter a known IP address that won't change? You'll also need to enter a subnet mask, just make it the same on each machine. In fact, since your Intranet doesn't show a connection to a DHCP router, you'll need to do this anyway.

This is for my Windows WiFi connection, you'd do it on your hardwire connection. Don't know the Linux method.

 

[OccamsRazor]

My problem is that I do not know how to set a 'stationary' IP address on the Raspberry Pis. I know how to on a Windows machine.
I can log into each Pi individually and run an ifconfig however, I do not know if it will have one since it will not be issued (in the intranet/hub configuration) without being plugged into a router.

 

[Sneakers]

My problem is that I do not know how to set a 'stationary' IP address on the Raspberry Pis. I know how to on a Windows machine.
I can log into each Pi individually and run an ifconfig however, I do not know if it will have one since it will not be issued (in the intranet/hub configuration) without being plugged into a router.

Temporarily plug it into any router, make the changes, and move it to the intranet.

Seems to me, and I'm trying to remember ancient history here, if there is no router, the DHCP device defaults to an address starting with 169. something...

If you see a 169.254. x.x address, it means that the DHCP server is not reachable. The PC will not work because there is not a router to or from that PC.

 

[OccamsRazor]

Think I will just hardwire the RPis into the router and retrieve their IPs from the setup menu. Then, I will just use the wireless Windows CPU to network into each of them and transfer files like that. I know that will work AND the hard wire connection between the 2 RPis will make it faster.

Thanks all for the ideas and assistance!

 

[Clem72]

If it's a hub, then there is no DCHP daemon, which means you should be manually setting the IPs.

 

[warneckutz]

Nerds

 

[PrchJrkr]

Nerds

IKR? I was going to jump into the fray, but I've been trying to purge my last few remaining brain cells of all the stuff I don't (and hopefully never will) use again. It sounds like he's got a plan!

 

[Kyle]

Nerds

No I’m still trying to figure out what he’s doing with raspberry pies.