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Comment: Re:Oh for fucks sake (Score 1) 611

by ArmoredDragon (#49748963) Attached to: The Economic Consequences of Self-Driving Trucks

as the ACA does contain measures to address how much is paid out to those services.

True, however they don't actually work. Does that make sense to you? I get it that you're biased and you really want it to work for idealistic reasons, but I'm afraid reality has to piss in your Cheerios. Haven't you noticed how a lot of investors are taking their money out of other stocks and throwing it into health care stocks? Here's a hint: While the rest of the market is expected to see a correction VERY soon, health care providers aren't expected to see their margins decline. Why? ACA basically guarantees that they're going to do better than the rest of the economy.

If that doesn't make sense to you, then sorry, but I can't help you.

Bye.

[/discussion]

Comment: Re:It's not a networking issue. (Score 1) 359

by ArmoredDragon (#49748153) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

IF there's no security

There's probably not security per-se, but I strongly suspect that a firmware update would have some kind of error detection that may panic somewhere along the line if say one of the layer 2 FCS didn't match after being transmitted across one of the lines, causing a TCP segment to get dropped. For that one pump it would work, but it would screw over the rest of them.

Comment: Re:It's not a networking issue. (Score 1) 359

by ArmoredDragon (#49740155) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

Not to mention none of your suggestions will work anyway if the destination IP address must remain the same single IP address assigned to all pumps, which appears to be the case based on the problem description. You can't differentiate between pumps if the update application on the laptop doesn't allow you to change IP addresses.

Good point. Though I'd make it even simpler (once configured) than what you're doing if that's the case. Use two switches, set a vlan for each pump, trunk that through a single cable to another switch located in the office, then create a switch port that goes to each different pump vlan. Just connect it to the respective port for each respective pump as you update.

Or if you really want to speed things up, skip the second switch, get the free version of VMware ESXi 5.5, configure its host interface in trunk mode, and create a separate VM for each pump and put it on the respective vlan. Then make all of the VMs use a common filer location that has the update files, that way you only have to copy the firmware image once, and you can switch from tab to tab in vSphere and just click the "update" button or whatever each time you switch.

Comment: Re:It's not a networking issue. (Score 1) 359

by ArmoredDragon (#49739031) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

Yeah that would actually work better because the host device might fail to send ARP requests to the switch with what I suggested (though what I suggested would work if the traffic originated from the laptop and wasn't needed after the ARP cache expires.)

But if you wanted to do it with say a switch that doesn't do VRF, and the host devices won't need to send ARP requests, then with my method the switch itself technically has no idea what the host IP address is, rather after it passes through the PBR ACL (policy based routing access control list) the source and destination IP addresses are changed without the need to configure their subnets.

I.e. say the device has an IP address of 1.1.1.1/24, and your SVI is configured as 2.2.2.2/30. You create a policy that says traffic aimed at 2.2.2.3 has its destination IP address changed to 1.1.1.1 and source address changed to 1.1.1.2 as it leaves the interface.

When 1.1.1.1 replies to that traffic to 1.1.1.2, it sends it ingress to the SVI. You then have an ingress policy that says that traffic destined for 1.1.1.2 has its source address changed to 2.2.2.3 and destination address changed to 3.3.3.3 (the IP address of the laptop) as it leaves the interface

ARP should be fine here so long as the first packet originates from the SVI (it will get the SVIs mac address,) however after the arp cache expires, the device might fail to initiate traffic in the other direction, which may be a concern depending on what exactly we're doing with the end devices. However even that can be solved by creating a secondary IP address of 1.1.1.2 on the SVI, like this:

conf t
int vlan 300
ip address 2.2.2.2 255.255.255.252
ip address 1.1.1.2 255.255.255.252 secondary

That *should* allow the end device to properly ARP the switch. And for each other SVI you can do the same, just use a different subnet range, making sure to stay within the /24 of the host device.

That of course, is an ugly hack, and VRF would be better.

Comment: Re:It's not a networking issue. (Score 1) 359

by ArmoredDragon (#49737905) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

Engineers have a code of ethics

I'm not aware of any code of ethics. Though the company I work for has a general saying that when you do an action, ask yourself if it's something that you'll want to be remembered for, which all employees do, even the management, accountants, etc.

Comment: Re:It's not a networking issue. (Score 5, Insightful) 359

by ArmoredDragon (#49737387) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

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.

Comment: Re:It's not a networking issue. (Score 5, Informative) 359

by ArmoredDragon (#49737179) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?

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.

Comment: Re:Oh for fucks sake (Score 1) 611

by ArmoredDragon (#49733281) Attached to: The Economic Consequences of Self-Driving Trucks

Oh, also the USA is, by practical definition, purely free market.

I say practical because there aren't any industries where the government owns the means of production unless you count interplanetary space probes, or military operations.

I also want to say manned space flight, but the private sector has recently entered that industry (though you may include it as the private sector doesn't technically do it on a commercial basis yet.) The private industry manufactures military equipment though (e.g. fighter jets are made by Boeing and others and purchased by the government.)

Most western countries have some kind of socialized medicine (i.e. in Canada, all medical personnel work for the government and are forbidden from running a private practice, whereas in the UK private practice is permitted but it's mostly only for rich people who can afford people who they believe do a better job than the NHS workers.)

However the US does not. In the US, "government paid" medicine comes in the form of an HMO type insurance that just pays all of your medical expenses to private companies, and then charges you almost nothing for it; but the private sector still owns the means of production. It only truly fits the definition of welfare and not socialism.

Side note:

When the ultra conservatives say the US has the best medicine though, I'm inclined to agree. If you look at countries with socialized medicine, virtually all of them have contracts arranged with private hospitals in the US where they send their people if their country doesn't have the facilities available.

Usually this is something super specialized. For example, their worst cancer patients that have a chance of recovery are sent to MD Anderson Cancer Center in Texas. Other fields such as Neurosurgery, Pulmonology, Cardiology, and other specialties for vital organs are often sent to Mayo Clinic or Johns Hopkins centers. Countries I know of who have sent their patients here for these include Canda, UK, Germany, and Sweden.

Where the US tends to look bad in the rankings are individual hospitals that mainly just serve ER patients who don't bother shopping around, so their service can suck but they can still bill stupidly high amounts. Because there are so many of these hospitals, it makes the average US hospital look less than stellar.

That said, knowing what I know about how socialism impacts other industries, I think it would be a mistake for the US to switch to socialized medicine. We do spend too much on medicine however. I think one way to fix that might be to add a bit of regulation stipulating that doctors and hospitals be required to show their rates for the most common services that they provide up front, and before you are provided any services, you as a patient are given the right to know what your bill will be BEFORE the service is performed if you just ask.

This would end hospital/ER sticker shock and billing errors (which are at something like 90%) and at the same time force medical staff to be more competitive on price. Even if you're insured, it would be preferable to shop around since most people have a deductible to deal with.

Also, in my opinion, the Affordable Care Act is only going to raise prices, and they're already high enough, because all it does is raise the demand for medical services without doing anything to address how much is paid out to those services.

Comment: Re:It's Jason Scott (Score 1) 121

He should have asked me a few years ago. I had a few CDs that are no doubt rare that I'm not sure if I have anymore. One of them was a beta copy of Microsoft's Allegiance (I was invited to the private beta) and the Shareware Quake CD that included ID's complete library of games, and all you had to do was download a keygen to play every single one of the full versions of those games for free.

I also had a big stack of CDs that included full versions of programs that used to be bundled with PCs (back before the era of when they just bundled crapware with them) but I'm pretty sure I threw that away.

Comment: Re:I see the master plan (Score 2) 121

Shareware can typically be redistributed, and in most cases the author specifically put language in saying that they even encourage you to do so. In fact if somebody ever took it to court, I think there's sufficient evidence that stamping the shareware label on anything means that anybody in the world is given a blanket license to distribute it as much as they want.

I actually used to have one of those Walnut Creek CDs that I bought from a software store in a mall. It was called Doom Fever, and had a crapload of stuff on it that was fun for me at the time because even though I had a 14.4kbps modem that I bought with my allowance, my parents refused to ever pay for internet access because they were afraid that just the mere act of getting online means that its easy for somebody to steal your identity and ruin your life (they watched the movie The Net and basically assumed that that kind of thing happens to people all the time the second they dial in with their modem.)

I did use my modem to play Warcraft 2 and Doom multiplayer with friends down the street a lot though.

"Pascal is Pascal is Pascal is dog meat." -- M. Devine and P. Larson, Computer Science 340

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