Here in the Oregon HQ formacosxhints.com , we ’ve got a few devices on our local internet . There are the Macs , of course , and a networked Brother optical maser printer , the AirPort Base Station , and our ( rarely used any longer , thanks toParallels DesktopandBoot Camp ) get on personal computer . Then there are the random thing that come and go , such as the occasional machine from my wife ’s office , or products for review , such as the Axis 207W wireless camera .
When I set the web up , I decided that I desire to practice still IP addresses for all the twist that are usually here , and then have active IP address assigned to irregular devices . This has worked well for me , as I ’ve memorized the IP address for our automobile and printing machine .
But sometimes I run into a problem when there ’s a equipment that I have n’t used in a while , such as the Axis photographic camera . It had been unplugged for a few weeks when I recently need to habituate it again . So I plugged it in , only to realize that I had no theme what its IP address was . Without the IP address , I could n’t reckon the camera ’s images nor change its configurations . ( Other than that , it was perfectly useful ! ) abruptly of reset it to the factory defaults , I thought there must be a elbow room to discover its name and address on my web .
After some digging , I find that the Unix commandpingoffers a solution . Usually , pingis used to send an “ echo request ” packet to a given host or IP speech . If the equipment is adequate to of respond ( and has n’t had that ability halt ) , then the equipment will respond with an replication response . you may see this for yourself in Terminal by typing this command :
You ’ll see a something like this when you go the command :
This will repeat until you tell it to stop by pressing Control - C. ( mark that many site will blockpingrequests , so you may not get any reaction at all . ) you’re able to do the same thing on your local meshwork , assuming you know the gimmick ’s IP computer address . On our web , for instance , our printer ’s IP address is 192.168.1.101 , and if Iping 192.168.1.101 , I ’ll see the same sort of production . But how canpinghelp if you do n’t know the machine ’s reference ?
Some adaptation ofpingsupport a “ broadcast ” pick , which will send a ping to every possible name and address on the web , and then list those machine that respond . Unfortunately , the version ofpingincluded with OS X does not let in that option . It does , however , have another way to do a broadcast Ping River : just broadcast a normalpingto a peculiar IP address on your web .
so as to do this , you necessitate to know two thing — your connection ’s IP speech setup and the subnet masque value . Both of these note value are easily find out in the web ascendancy panel , in the IP Address and Subnet Mask fields , severally . In my case , my Mac ’s IP address is192.168.1.77 , so the connection is using a192.168.1.xxxsequence , and the subnet mask is255.255.255.0 . The special ping destination can be figured out by taking any zero values from the subnet mask , changing them to255 , and then putting them into the same relative position in the IP address field of view . In my case , the last digit of my subnet masquerade is zero , so I change that to 255 , and put it into the last position of my IP speech , then knock that reference :
If my subnet masque were255.255.0.0 , then the Ping River address would be192.168.255.255 . When I ping this particular 255 destination , I get a answer from every twist on the web that can respond to ping request :
Again , this will reiterate until you weigh Control - C. Since I know the addresses of my Macs and the pressman , I was able to see that the192.168.1.57address was n’t unremarkably there . Hence , that was the tv camera ’s IP address .
But what if that ’s not enough ? What if you ’ve got a quite a little of devices , and you ca n’t really be certain which is which ? After running the broadcastping , you may then run thearp(which is scant forAddress Resolution Protocol ) command . If you usearpwith the - aoption , it will show everything that it knows about . In my case , it take care like this :
The machine I ’m start the statement from ( 192.168.1.77 ) does n’t show in the list , but everything else does — admit the MAC address , which is the serial of numbers and letter sort out by spaces . The MAC speech unambiguously identifies each piece of hardware , and can ordinarily be found somewhere on the equipment itself . In OS X , for case , it ’s on the Ethernet tab of the Networking ascendance board ( if you ’re on a wired electronic web ) . ironware devices , such as photographic camera , might have the MAC address on a visible label . With the MAC destination in hand , you should be able to find every gimmick on your local electronic internet .
A few of notes . First , if you ’re in an office , particularly a large office , I wouldnot recommendusing this control — you may put up the anger of the system admin if you canvas every gimmick on a 500 unit connection ! Second , if you ’re on an AirPort web and you have n’t reconfigured anything , the default IP call dodging is10.0.1.xxx , so the particular broadcast ping address would be10.0.1.255 . Finally , I ’ve modified all the IP and MAC addresses in this clause , in the pursuit of obscuring the real addresses of my machines ( though they all live behind a firewall , plainly ) .
felicitous machine searching !
