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Networking Upgrades IT

Ask Slashdot: Best Way To Solve a Unique Networking Issue? 384

New submitter petro-tech writes: I work as a service technician, maintaining and repairing gas pumps and POS equipment. In my day to day activities, one that consumes a ton of time and is relatively regular is the process of upgrading the software on pumps. This is done by connecting to the pump via direct ethernet from my laptop, then running a manufacturer-provided program that connects to the device and pushes the new software. Some sites have 8+ pumps with 2 devices in each, and at 20-30 minutes apiece this can be quite time consuming. Unfortunately the devices are not actually on a network, and as such cannot be updated remotely, also since they are not on a network, they are all configured with the same IP address. Additionally the software doesn't allow you to specify the adapter to use. I would like to be able to get to a site, connect a cable to each pump, and load them all at the same time. The only way I can figure to accomplish this with the software we've been provided is to do this: Get a 16-port powered USB hub, with a usb-ethernet adaptor in each port; Set up 16 VM's with extremely stripped down XP running on each, with only one USB-ethernet adaptor assigned to each VM; Set XP to boot the application for loading software as its shell; and load each device that way at the same time. Is there a better way to accomplish this?
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Ask Slashdot: Best Way To Solve a Unique Networking Issue?

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  • by xxxJonBoyxxx ( 565205 ) on Wednesday May 20, 2015 @12:33PM (#49736793)

    >> Unfortunately the devices are not actually on a network

    So...it's not a networking issue?

    • by antiperimetaparalogo ( 4091871 ) on Wednesday May 20, 2015 @12:52PM (#49737063)

      >> Unfortunately the devices are not actually on a network

      So...it's not a networking issue?

      No, it is a networking issue; nodes are nodes, even if not connected - what the guy does normaly is a network with 2 nodes, now wants more.

      • by gstoddart ( 321705 ) on Wednesday May 20, 2015 @02:35PM (#49738369) Homepage

        But the reality is from the description of this, the manufacturer has done a crap job of building the "networking" part of this, and if you start trying to be clever and hook it up to an actual network you might really fsck it up.

        So, imagine some field tech decided he'd rather find a clever new way to fix things, and then hoses (pun intended) the pumps because he's doing something which the pumps can't actually be made to work with.

        Who the hell do you think is going to fix it?

        You can call it a networking problem, but I would suggest if the manufacturer has given them all the same IP address ... these things aren't designed to be "networked" in any meaningful sense of the word.

        Do you really want to run the risk of fucking up the pumps because you think you have a solution which works?

        Because setting up a bunch of VMs so you can hook them up in a clever way and try to do this in parallel sounds like you have a better chance of it going wrong than going right.

        It may use some networking technology in a limited way, but it isn't a networked device ... from the sounds of it they use that networking port as little more than a serial connection. And if you start trying to connect them all at once with some fancy setup of your own, you have no frickin' idea how it's going to work or what will happen.

        You don't want to explain to the gas station owner why he has no working pumps and why the company who makes them wants no part of what you broke by doing it in an unapproved way.

        • Alternatively, you could say the manufacturer has done a good job of eliminating networks as a source of malware.

    • by ArmoredDragon ( 3450605 ) on Wednesday May 20, 2015 @01:02PM (#49737179)

      I think what he's asking is whether or not he can network them together even though they all have the same IP address. And the answer is yes.

      As a network engineer, I can think of a way with a Cisco catalyst switch, OR, a linux box with multiple ethernet ports:

      For a Cisco switch, get a layer 3 switch, enable ip routing, put each switch port on a separate vlan, create an SVI for each vlan that is on a /30 subnet using the first address of that subnet. Create an access control list so that all traffic that goes ingress to the second IP address of the vlan subnet has its destination address changed to the static IP address of the equipment and the source address changed to be the IP address of the SVI, and then change all egress traffic from the second subnet IP to change the destination address to match that of your laptop and the source address to match that of the second IP address in the subnet.

      For a linux box you'd do the same thing, only using SNAT and DNAT in iptables.

      Effectively what you're doing is creating a NAT table that allows you to uniquely address each device, without actually changing the IP addresses themselves to become unique.

      If you're not very affluent in networking, the above will sound VERY confusing, but trust me it can be done.

      • by g0bshiTe ( 596213 ) on Wednesday May 20, 2015 @01:09PM (#49737279)
        I think you like many are missing the main question and would in fact be the only question I'd ask him and it would determine if you should continue or stop right there.

        Are you paid by the hour? If yes, what the actual fuck are you thinking?
        • by ArmoredDragon ( 3450605 ) on Wednesday May 20, 2015 @01:17PM (#49737387)

          I think you like many are missing the main question and would in fact be the only question I'd ask him and it would determine if you should continue or stop right there.

          He offered me a problem, so I offered him a solution. I'm an engineer, I solve problems. He didn't ask for security (which this can be secured by the way, but that involves a bit more discussion, which I don't have enough information to counsel on.)

          Are you paid by the hour? If yes, what the actual fuck are you thinking?

          Have you ever heard of lean principles? Basically by reducing the number of steps it takes to perform a job, you reduce the chance of human error (thus increasing your product's quality) while also lowering costs. Managers who employ this technique love it when employees make suggestions like this that actually work.

          Does his boss appreciate that kind of thing? I don't know, but if I was his boss, and he brought this kind of solution to me, that would gain him some extra brownie points. Instead of having him do that time wasting work, I'd maybe give him better jobs to do that may even pay more, if I had them available.

          • Basically by reducing the number of steps it takes to perform a job, you reduce the chance of human error (thus increasing your product's quality) while also lowering costs.

            However, the chance of a human error borking 16 pumps at one time increases dramatically.

            • by mjm1231 ( 751545 ) on Wednesday May 20, 2015 @01:53PM (#49737849)

              I used to tell this to my boss all the time when we had to make changes to all 500 PC's on the domain, and walking from PC to PC to do it manually was still standard practice. If I screw up with a script, at least they'll all have the same mistake, instead of 500 different mistakes.

            • by TWX ( 665546 )

              Basically by reducing the number of steps it takes to perform a job, you reduce the chance of human error (thus increasing your product's quality) while also lowering costs.

              However, the chance of a human error borking 16 pumps at one time increases dramatically.

              That depends on how much direct control the technician has over the pumps. If the technician doesn't really make any choices and is just conducting rote firmware updates or pushing out prewritten configurations then short of b0rking the process itself he can't do much to break them.

              As for the process itself, I advocate a low-tech solution. Go get a bunch of older small Netbooks with ethernet jacks on them, set up a box in the van or service truck as the wifi controller, connect those netbooks to the wi

          • "Are you paid by the hour? If yes, what the actual fuck are you thinking?"

            Perhaps he is thinking he can get a week's worth of work done in 2 hours. Assuming he didn't bother telling anyone about his new technique, he can now go play golf or nap the rest of the week while the boss thinks he is "hard at work".

        • That's not the important question.

          These are gas pumps. Should he network them together? Is the question.

          Though I do see an advantage of a closed local network for the pumps that doesn't have outside access. ( access only through a specific port.

          • by suutar ( 1860506 )

            It sounds like he's only networking them long enough to update them. He brings the hardware, plugs in the pump, does his thing, unplugs. He just wants to parallelize; de-networking the pumps is still a step.

          • by TWX ( 665546 )
            Be careful, the Cylons can infiltrate computer networks. May be better to keep them separated.
        • Are you paid by the hour? If yes, what the actual fuck are you thinking?

          Because who wouldn't want to keep doing a tedious job over and over as long as the income is steady? /s

          Even if this person is a lazy fuck (which I suspect he isn't), he still has an incentive to solve this problem. He could automate the software load for all the gas pumps (minimizing the amount of work he needs to do), and sit in his car playing cell phone games for the amount of time it normally takes to do it the tedious way.

          It pays to be efficient whether you are a lazy fuck or someone who wants to get

      • A competent, helpful answer in the third post.

      • Similar, but less complicated...

        On a Cisco catalyst,

        script this:

        conf t
        int g0/1
        no shut

        ping and program

        shut
        int g0/2
        no shut

        ping and program ... lather rinse repeat
      • by Lumpy ( 12016 )

        Or, simply configure the pumps to have different IP addresses. Does his boss pour gasoline on him and set him on fire if he changes their IP addresses?

      • by rudy_wayne ( 414635 ) on Wednesday May 20, 2015 @01:35PM (#49737629)

        I think what he's asking is whether or not he can network them together even though they all have the same IP address. And the answer is yes.

        As a network engineer, I can think of a way with a Cisco catalyst switch, OR, a linux box with multiple ethernet ports:

        Yes, there are a few possible solutions, but I'm surprised that nobody has mentioned the biggest barrier to implementing any of them:

        Trying to connect to 8+ pumps at the same time is going to require running 8+ ethernet cables from a central location to each pump. You're going to have cables all over the place, and unless it is done while the gas station is closed it means people driving over the cables, stepping on them, tripping on them and yanking them out of the socket, etc........

      • by Anonymous Coward on Wednesday May 20, 2015 @01:36PM (#49737635)

        As a network engineer, I can think of a way with a Cisco catalyst switch, OR, a linux box with multiple ethernet ports:

        That's way too much complication for what he needs.... Assuming each pump has a unique MAC, all you need to do is a bit of work with ARP tables. Collecting MAC's should be easy, cable up and try and ping the standard IP address... They will all reply to the ARP request. Scrape up the MAC's, dump them into his Virtual Machines running the update software to map that MAC to that IP in the VM and make the assignment never expire. Do your update, the software is unlikely to know the difference... For this approach, you only need a switch/hub and network cables.

        My other idea was to build a VM box with a separate network segment for each VM, then map these all though a Linux VM that puts them on an 802.1q VLAN. Go buy a *cheap* managed switch (and I do mean cheap) and create one trunk port with each other port on a separate VLAN untagged. No need for an expensive Layer 3 switch... In fact, you could set it up on a cheap consumer router running OpenWRT as long as the switch supports VLANs, in which case the most expensive part of the hardware would be the network cabling..

      • by Krishnoid ( 984597 ) on Wednesday May 20, 2015 @01:48PM (#49737791) Journal

        If you're not very affluent in networking, the above will sound VERY confusing, but trust me it can be done.

        I think you mean 'fluent', as in you understand networking well. Then again, you could mean that this is expensive, in which case, 'affluent' would be correct. Although, the original problem refers to programming pumps, so it could be 'effluent'.

        Glad I could clarify that.

    • So...it's not a networking issue?

      That's what makes this networking issue so unique.

    • Get a switch which supports VLANs, 1 vlan on each port and the trunk on your laptop. Then run the mfg's software inside virtual machines, each of which has one of the vlans connected to its virtual ethernet, using the mfg's IP address. Now you can run all the updates in parallel.

      The better solution is for the mfg to give you software and a configuration that does not suck. But if you're stuck with it, the above will work just fine.

    • not a central one at this point. I will bet you a gallon of Ethyl that the pumps have hardcoded authentication, and the software probably has enough holes you could drive the Indy 500 through.

      you don't want that on a network. not even for a little bit. you want that locked behind a panel. if there is no security, all you have is obscurity.

  • by phantomfive ( 622387 ) on Wednesday May 20, 2015 @12:34PM (#49736811) Journal

    Unfortunately the devices are not actually on a network, and as such cannot be updated remotely, also since they are not on a network,

    It makes me feel good to know that something in this world is still air-gapped.

    • by Anonymous Coward on Wednesday May 20, 2015 @01:23PM (#49737449)
      They aren't actually air-gapped. They are on a two-wire control network with the POS device - which is why the dispenser (NOT PUMP) can be stopped remotely from the POS. It is also how price changes, pre-authorizations (I want $20 on #7) are done. But that network doesn't allow firmware updates, just control.

      The original submitter probably doesn't know much about these if he calls them pumps. A station has only one pump per grade of fuel (although in some rare cases of multiple tanks even when they are connected together they may have 2 pumps per grade of fuel). The heads that people call "the gas pump" are dispensers only. They don't create the pressure that generates flow. He is reprogramming / flashing the dispenser control heads. It is normal for the ordinary consumer to call these things "gas pumps" - but people who work in the industry generally know better and would call them dispensers.
      • by uncqual ( 836337 ) on Wednesday May 20, 2015 @01:38PM (#49737667)

        Although, perhaps the original submitter called them "pumps" rather than "dispenser control heads" because they assumed that was what most /. readers would understand. Generally it's best to communicate in the language your audience understands unless it confuses others -- and you, allegedly knowing how these things work, seem pretty confident that you understood what the submitter meant. Mission accomplished.

      • by jbengt ( 874751 )

        A station has only one pump per grade of fuel (although in some rare cases of multiple tanks even when they are connected together they may have 2 pumps per grade of fuel).

        Actually, it can go either way. You can buy dispensers with built-in pumps - one pump per dispenser per fuel type, with suction piped to the tanks, or you can drop a pump into each fuel tank, with discharge piped to the dispensers. You do have to be careful about minimum positive suction head if you go with a dispenser-mounted lifting

  • by rwa2 ( 4391 ) * on Wednesday May 20, 2015 @12:39PM (#49736885) Homepage Journal

    ... is no.

    The thing you propose sounds fine. But do they really want to upgrade all of the pumps at once? Sounds like a great way to brick an entire facility.

    The only "improvement" I could think of would be to set up some kind of cheap router that can do MAC address filtering, that way you can set up the router to allow only one of each pump to show up as that one silly IP address at a time on a switched network. But then you'll still be able to only do one at a time.

    The "right" way to do this is just throw money at the problem and attach a real computer to each pump, with a separate interface to talk to the static IP. Maybe something as small as http://www.fit-pc.com/web/prod... [fit-pc.com] or just some generic mini-ITX board in a telecom chassis or whatever.

    • Not only that, the gas station may not want more than 1 pump down at a time.

    • That's exactly what I came here to say. Why this would save OP time...it will cost the station money. The current setup means one pump is down at a time. His proposal means all the pumps at the station will be down, or even if he is more responsible and does half and half, half of them will be down. This is unacceptable from a cost-benefit perspective (no way is his time savings worth the loss in sales) and from a customer service perspective. Just forget it and bring a book. You're getting paid, right? Un
    • Besides, if you can do it in 1/16th of the time, you might find your maintenance budget get slashed to 1/16th of previous year/quarter.

      From what you described, it seems you/they allocate about a day to upgrade each station (16 units at 0.5 hour each.) Beats driving around in traffic to 16 different stations a day, too.
      • Besides, if you can do it in 1/16th of the time, you might find your maintenance budget get slashed to 1/16th of previous year/quarter. From what you described, it seems you/they allocate about a day to upgrade each station (16 units at 0.5 hour each.) Beats driving around in traffic to 16 different stations a day, too.

        Don't be silly. The maintenance will still take just as long. He'll just have much more time to focus on his real priority - Clash of Clans.

  • Solution (Score:5, Informative)

    by TooMuchToDo ( 882796 ) on Wednesday May 20, 2015 @12:43PM (#49736951)

    1) Get a managed switch
    2) Configure all ports but one to be on their own VLANs
    3) Configure one port to be a trunk port
    4) Configure your laptop or other computing device to support trunking
    5) Configure your virtual machine so the entire process is scripted. It should boot, execute the upgrade procedure, and then provide logging for the process to you.
    6) Start VMs, with each configured on one of the VLANs.

    Done.

    • by hjf ( 703092 )

      This. It was the first thing that came to mind.

    • by skids ( 119237 )

      Yes, this. There are a good number of cheap managed switches and that would collapse the octupus USB hub into a neat little package.

      (Actually you can also get some of the cable modems to vlan on the switchports, depending on the chipsets, but that's a bit more hinky)

      The other possibility is to play ebtables tricks based on the device MAC address, but you still end up needing a hub, so just go with the managed switch.

  • Easy! (Score:5, Insightful)

    by WPIDalamar ( 122110 ) on Wednesday May 20, 2015 @12:44PM (#49736963) Homepage

    Get 16 laptops.

  • Probably the way (Score:5, Interesting)

    by phantomfive ( 622387 ) on Wednesday May 20, 2015 @12:45PM (#49736967) Journal

    The only way I can figure to accomplish this with the software we've been provided is to do this: Get a 16-port powered USB hub, with a usb-ethernet adaptor in each port; Set up 16 VM's with extremely stripped down XP running on each, with only one USB-ethernet adaptor assigned to each VM; Set XP to boot the application for loading software as its shell; and load each device that way at the same time.

    That might be the best way, because you are limited by the software they gave you. Might consider trying Linux and Wine to save space. If that works, then you can load 16 raspberry pies into a briefcase and run it from there (I've seen similar operations for wireless monitoring).

    If you actually do build that setup, please take pics because it sounds kind of cool.

  • by Ariastis ( 797888 ) on Wednesday May 20, 2015 @12:45PM (#49736977)

    Go on FleaBay and get a few older laptops for dirt cheap ; set one up with your software and copy it to all the others.

    You can now do thay many pumps at once, and if one has a problem it wont screw up the whole lot.

  • Create 8 battery operated arduino's whose sole purpose is to translate and then broadcast the single IP Ethernet to unique IP on a wireless network, run a local ap, then I'm sure there are apps/scripts that will allow you to sandbox the OEM app allowing the reversing of the IP translation back to the original and running multiple concurrent independent instances(no VM required), i did this with outlook prior to it allowing multiple exchange accounts, although didnt tackle the ip routing. Then sit back and g
    • i did this with outlook prior to it allowing multiple exchange accounts, although didnt tackle the ip routing.

      The routing is the hard part.....it's like some kind of weird reverse-NAT. It seems like there should be some simple IP-Tables command to do this based on MAC address, but I don't know what the command would be. Then he could run multiple instance of the same software (depending on the software).

      I don't think there's a way to set up that kind of routing in Windows, though.

  • I guess you could throw each one behind some sort of NAT router; maybe something like a Raspberry Pi, so that to the actual LAN they each have a unique IP. But even going for a low end computer-on-a-stick solution, you'll need a second USB ethernet adapter, or ethernet-to-WiFi bridge, not to mention it sounds like they are still air gapped, so can you reasonably get cabling to the pumps? So you're talking here about 20-30 NAT routers plus cabling. A big cost, with some security implications that need to be

  • Don't (Score:5, Interesting)

    by HornWumpus ( 783565 ) on Wednesday May 20, 2015 @12:51PM (#49737053)

    If you fix this problem they will more then likely fire you. Nobody likes a smart-ass. They know what your time is worth, likely not much. Just do it the slow way.

    Seriously, you are an upgrade monkey.Just monkey on and look for a better job where you can use your skills and you will be _paid for them_.

    Alternatively: If your employer is contracting to do the upgrades, figure out how to do it in 25% of the time and take the business from them. They don't own their clients, but likely think they do.

  • I think you could configure each port on the switch with a different default VLAN and plug those into the terminals (e.g. Port 1 gets VLAN 1, Port 2 gets VLAN 2, etc). That will by default separate each port into a separate network. Then use VLAN tagging on your XP VMs that you were going to spin up, so they each are effectively connected to a separate port on the switch (e.g. VM 1 is tagged for VLAN 1, VM 2 is tagged for VLAN 2, etc).

    This is just the high-level details of what you'll need to do. Most lower-end consumer grade switches don't have VLAN support, so you may need to spring for a better switch, and make sure your VM software supports VLAN tagging.

  • by mschuyler ( 197441 ) on Wednesday May 20, 2015 @01:00PM (#49737149) Homepage Journal

    OP said "day to day" activities. He's updating one pump at a time. What are the other pumps doing? Dispensing gasoline. To update all 16 pumps at once would render all 16 pumps out of service for half an hour. That is simply unacceptable for the station. They would not want to just shut everything down and eliminate a half-hour's worth of revenue from 15 pumps just so OP is not inconvenienced.

    This is a typical IT viewpoint. We have a technical problem to solve, and to hell with the users. They're just in the way of our supreme elegance anyway.

    • This is a typical IT viewpoint. We have a technical problem to solve, and to hell with the users. They're just in the way of our supreme elegance anyway.

      This is a typical user whine. Ask the user to log off at the end of the day to allow the computer to be accessible during the nightly maintenance window, it becomes a life-and-death struggle for them to log in the next morning, launch their applications, grab coffee and -- gasp! -- talk to a coworker in the hallway. And then get mad when all the systems are rebooted during a three-day holiday weekend to deploy the security patches.

    • Yeah it's hard to imagine having a bunch of nework cables strung over a gas station being acceptable. Maybe just doing a cluster of pumps would be a better goal.

    • You are quite right.

      Then again, he also mentions that "some sites have 8+ pumps with 2 devices in each".

      Just being able to update both devices in a single pump should already cut his worktime in half, while having two stations down instead of one should not affect the business very much.

    • OP said "day to day" activities. He's updating one pump at a time. What are the other pumps doing? Dispensing gasoline. To update all 16 pumps at once would render all 16 pumps out of service for half an hour. That is simply unacceptable for the station. They would not want to just shut everything down and eliminate a half-hour's worth of revenue from 15 pumps just so OP is not inconvenienced.

      This is a typical IT viewpoint. We have a technical problem to solve, and to hell with the users. They're just in the way of our supreme elegance anyway.

      Not to mention the lawsuit when a customer trips over the cat5 obstacle course.

  • Are you paid by the job or by the hour?

  • What type of idioticly designed pump takes half an hour to run a software upgrade?

    Let me guess: Some useless manager thought it'd be easier to stick a full-fledged PC running Windows inside every pump than it would be to hire someone who can do proper embedded software development?

    • What type of idioticly designed pump takes half an hour to run a software upgrade?

      According to the OP, the update process involves "running a manufacturer-provided program that connects to the device and pushes the new software."

      I don't think it's too hard to guess what level of software quality is provided by the pump manufacturer.

  • All the pissing matches about IP access for gas stations were covered in a past post.

    http://it.slashdot.org/story/15/01/23/1856201/us-gas-stations-vulnerable-to-internet-attacks/ [slashdot.org]

  • Basically what I wonder is if although the units are locked down to a specific IP is the software used to do the uploading?
    If not, you can use arp to give the machines a new IP against their MAC addresses. Then run multiple instances of the install software and point at each IP.

    https://technet.microsoft.com/... [microsoft.com]

  • This might half the time required. You say you have a VM already on the laptop. Get a handful of external ethernet adapters. I think the best number will be in the neighborhood of 4, but learn with 2.

    Run the VM and have one adapter present in each VM. Connect to device inside the pump. Start the next VM. etc. This is still a 2-node network, each instance will have a "fail safe" in an error will stop the one instance. With a typical gas station having 2 double pumps per island having 4 connections mea

  • by Etcetera ( 14711 ) on Wednesday May 20, 2015 @01:24PM (#49737473) Homepage

    Dear Lord...

    You have an airgapped network that prevents remote access, reducing the question of security to one of physical security... which is typically handled with big locks, cameras, 24 hour staffing at the gas station, and maybe men with guns if it comes down to it.

    Why would you network these together and create an avenue for simultaneous, surruptitious hacking and attacking of your industrial equipment?

    Be thankful you have a job, and don't let the SysAdmin's (natural, and usually good) desire for laziness and efficiency to lead to a future security issue justified by convenience.

  • You know I'm all for open source but if you have a proprietary system that's vendor supplied, contact the vendor.

    Make it a time/cost/material problem...

    Yes, there is a technical work around for this, but if the firmware update is this half-assed you have other issues.

  • I've built a fair number of hypervisors, both VMware and Hyper-V. The hardware required to run 16 VM's concurrently is quite substantial. Good luck running 16 instances of Windows XP on a laptop!
  • by aaarrrgggh ( 9205 ) on Wednesday May 20, 2015 @01:40PM (#49737681)

    Sometimes, for diagnostic purposes I also need to add a second read head to the credit card scanner. It would really be helpful if I could add this to the network, along with the keypad's diagnostic port. Any ideas?

    In all seriousness though, there are some real fire protection issues with taking cables from the pump zone elsewhere. Everything in and out needs to be properly sealed to prevent explosive vapors from entering into a non spark-resistant system.

  • You'd need a configurable switch, which can run a couple hundred dollars. THen you can put each port of a switch on a seperate VLAN. Should work.
  • Network the pumps. Push the software one at a time. Lay off the tech. Problem solved.

  • by mjm1231 ( 751545 ) on Wednesday May 20, 2015 @01:56PM (#49737891)

    I can't believe nobody has posted the most obvious solution yet. Upgrade to IPv6.

  • Hello-
    If the 16 port switch is a SMART switch, you can, make the last port a TAGGED port, that carries tagged vlan traffic.
    Make each of the other ports (except number one) an UNTAGGED vlan. (keep number one stock so you can access the switch!)
    Maybe reserve one for the windows box.
    Then, on your computer, run a linux instance with vlans configured, like eth0.2, eth0.3 openwrt would be great for this, you can run it on a little router or a VM.
    On the linux box, (openwrt) set up address translatio

  • by jpellino ( 202698 ) on Wednesday May 20, 2015 @02:10PM (#49738063)
    Instead of by the device. Problem solved!
  • by netsavior ( 627338 ) on Wednesday May 20, 2015 @02:14PM (#49738113)
    I am having trouble with my billiards table, could you please tell me the best way to keep my football bat sharp so that my chlorine levels stay consistent?
  • by Bitmanhome ( 254112 ) <[bitman] [at] [pobox.com]> on Wednesday May 20, 2015 @05:36PM (#49739795)

    Why 16 VMs? If you're looking to learn VMs and/or advanced networking, then sure go that route. If you're just looking to save some time, just get 16 old laptops or netbooks with ethernet.

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