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Will the Serial Console Ever Die?
simpz writes "Will the serial port as a console connection ever be displaced — especially for devices such as switches, routers, SAN boxes, etc.? In one sense it's a simple connection. But it is the only current port that, in order to use, you need to know about wiring / baud rates / parity, etc. It has non-standard pinouts. And it is becoming too slow to upload firmware to dead devices, as the firmware updates get larger. Also, the serial port is rapidly disappearing from new laptops — which is where you often really need it, in data centers. Centronics, PS/2, and current loop are mostly defunct. Is there any sign on the horizon of a USB console connection?"
It calls out to you.
The great thing about a serial console is that it doesn't take long to figure it out. And you only need 3 wires to get there.
Another nice thing about it is that it's point-to-point, so you don't have to worry about your signals getting lost.
Heck, you can create a serial interface from discrete components if you're really into fun.
So use your serial console for what it's intended to be used for: emergencies and initial configurations.
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I upload firmware and program various devices at work via USB or TCP/IP - and it is great because the connections are fast. However, when something goes very wrong with the devices, the RS232 port always works. Also, being able to get serial data just by listening to a couple pins is far easier than trying to deal with USB connections/drivers you have no clue about.
When it comes down to it, serial works, its easy and it's a life saver.
Other than cisco routers and switches
Are you serious? The only examples anyone on Slashdot can find seem to be routers and switches? The reasons RS232 isn't going away is because an awful lot of industrial automation equipment (large and small-scale) still uses it. Why? Because a) all of the existing industrial automation equipment uses it, so new equipment is designed to be compatible with existing interface and control systems, b) it has proven itself to be incredibly reliable over the years, c) it's cheap (in terms of money, but also in terms of the amount of supporting hardware required). Also, while it may not be fast enough to transfer huge firmware images or run high-bandwidth stuff like video over, it's fast enough for what it's used for. If a firmware update takes 5min to do on a $100,000 piece of factory equipment, so what? The company probably spent a month planning for the upgrade, and will spend a week testing it after the update to make sure it still meets performance and safety requirements before re-deploying it anyways. There are billions of dollars invested in RS-232 by some highly conservative companies that don't change things on a whim, when a complication arising from an unnecessary change could cause 5-figure-per-minute damages or loss of life.
Why is RS-232 still around? Because it ain't broke, and it don't need fixin'!
Outside of Real Serious Stuff(if your job involves oil rigs, SCADA, legacy devices that Google has never heard of this probably means you), I strongly suspect that "serial" in the sense of "DE-9 or DB-25 connector that won't freak out when exposed to the full +/- 12(or even a touch more in some cases) volts that serial used when men were men and cable runs were long" is not so long for this world, outside of a few legacy niches.
On the other hand, "serial" in the sense of "a few pins carrying something that looks like rs-232 at whatever voltage this device's logic runs at" or "device has a USB connector; but that just means that they slapped an FTDI or Prolific chip on a serial design" will be more or less immortal. Even in high volume consumer devices, where it isn't supposed to be user accessible, you can generally find a logic-level serial connection somewhere, though it may not be labeled or have any sort of connector soldered in. It costs almost nothing and can save you from having to JTAG your way out of (most) of your mistakes. When designed to be accessible, it is ideal for dealing with initial configuration for devices that communicate primarily over ethernet.
Not much really - it only takes a very minimal stack to do simple things like TFTP or Telnet. Back in the mid 90's We used do to do this on '186 class stems in a few k of code. Its also easy to do a very simple low level UDP based thing - that that would be a bit proprietary.
I agree that serial ports are useful. What I'm suggesting is that the best alternative is Ethernet, not USB.
Jibe!
I'd hope these days a big honking server mobo would at least support booting from USB key.
Most of them do--but you have to realize that it took Microsoft until 2008 to release a server OS that doesn't require floppies to load RAID drivers.
Then again, it's hard to take anyone seriously that uses Windows in a server role.
Game! - Where the stick is mightier than the sword!
Serial is essential! It's cheap, simple, lots of hardware support it, and there's minimal firmware support needed for it. If you've got 8K RAM and runs at 1MHz, you don't want to waste it on a bloated USB driver. Serial port works from an interrupt context, so you'll be able to use it many times where USB can not work (say your OS is busted and you need to debug it).
Serial port isn't used because we're Luddites, but because it works.
Now if things had standardized on external I2C or SPI ports, that could work. But USB is just bloatware in comparison.