Setting up a multi-card serial server

[dk_netsvil]

Just about everything in my data center has COM port access to one degree or another and I want to build a serial server to allow me access through a universal portal. I've got a PC dedicated to this purpose running FreeBSD 7-STABLE, and I've got 4 PCI cards with 2 COM ports each that use the Moschip 9835 chipset.

I've been looking for examples of something like this online for a couple days with no real luck and was interested in knowing if anyone's already accomplished this and/or if anyone can point me in the right direction.

Edit: I'm interested in the area of serial console redirection

[Darwimy]

What exactly is your problem? If the ports are seen by BSD then I would just connect to the server using SSH and then use 'tip com1' or similar.

[dk_netsvil]

My goal is to have users login to this serial gateway and be automatically redirected to the COM port on which their device is physically attached.

[ai-danno]

I have attempted something similiar in OpenBSD (I want a number of switches and routers accessible via console), with 4.2. I have had problems.

I've been able to get the four-port serial card (mos 9835 like yours if I'm not mistaken) recognized and I get a grand total of ONE of those four ports to work.
I don't know if the system is finding confusion because they all answer on the same IRQ, or what.

I am going to test out the same card on 4.3 and 4.4 (when it comes out), so I'll try to remember to post back here when I do my testing.

Here's the portion of my OBSD 4.2 dmesg- it sees them all, so why can I only hit the first one!?!?!

puc0 at pci0 dev 14 function 0 "NetMos 4S" rev 0x01: ports: 4 com
pccom3 at puc0 port 0 irq 5: ns16550a, 16 byte fifo
pccom4 at puc0 port 1 irq 5: ns16550a, 16 byte fifo
pccom5 at puc0 port 2 irq 5: ns16550a, 16 byte fifo
pccom6 at puc0 port 3 irq 5: ns16550a, 16 byte fifo

[BSDfan666]

I don't know what you mean by "hit", but there have been lots of changes since 4.2, i.e: in 4.4 pccom(4) was discontinued and com(4) is now used.

[ai-danno]

You don't know what I mean by "hit", eh? I'll let you take a wild guess

[BSDfan666]

Originally Posted by ai-danno

You don't know what I mean by "hit", eh? I'll let you take a wild guess

Tech abuse should be a crime...

[darkmark]

On freebsd you can run a very reliable console server using :

conserver-com-8.1.16|/usr/ports/comms/conserver-com|/usr/local|Application that allows multiple users to watch serial consoles|/usr/ports/comms/conserver-com/pkg-descr|kuriyama@FreeBSD.org|comms|||http://www.conserver.com/|||

(ports INDEX line)

I ran two 8 port pci cards on one machine that were supported under the puc driver. In many ways it was way better than some of the commercial solutions.

[dk_netsvil]

I may give that a shot - for the time being I'm struggling to overcome the same issue ai-danno describes: only one port is functional and the others are inert. When I replace my quad-port cards with single-port cards I have no problems.

[darkmark]

Originally Posted by dk_netsvil

I may give that a shot - for the time being I'm struggling to overcome the same issue ai-danno describes: only one port is functional and the others are inert. When I replace my quad-port cards with single-port cards I have no problems.

All the serial devices on the card probe at startup then, i.e. you see them during kernel boot?

FreeBSD would occasionally have the problem since many of the multi-port cards share an interrupt and the puc driver wasn't mapping the devices properly, and only one port would show up. Sometimes it would just require the correct modification to pucdata.c to get it to work.

[ai-danno]

That's the problem I'm having... all recognized on the same interrupt, but only one seems to map.

As I stated previously, I'd get back when I had tried it on 4.3 ... and the same thing happens on 4.3.

Thanks for the heads up on conserver- it got me to check OBSD packages for such a beast, and in fact, it exists- so I'll be installing that on the 4.3 box and will let you know how it goes.

The thing that gets me... and maybe it's due to ignorance on my part (probably) is that there isn't some easy-to-find device mapping that tells you what the filename handles the devices from the dmesg (save the NICs, they show that just fine) are actually mapped to. So if pccom1 through pccom4 (and yes, since it's 4.3 it's not been switched to comx yet) show up in the dmesg, how can I be sure which cuaxx each one is actually mapped to?

[BSDfan666]

COM1 == {pccom,com}0 == /dev/{tty,cua}00
COM2 == {pccom,com}1 == /dev/{tty,cua}01
COM3 == {pccom,com}2 == /dev/{tty,cua}02

Pretty simple stuff.. it's documented in both pccom(4), and com(4).

I can't comment on your problems with puc(4) devices, but.. it might be worth sending a bug report.. complaining about a bug isn't as effective as reporting it. (And testing the LATEST version of the code base..).

They're preforming an audit of all old bug reports as we speak, so.. they're definitely paying close attention to bug reports.. send one, volunteer either time or a card.

http://www.openbsd.org/report.html
http://marc.info/?l=openbsd-bugs

[BSDfan666]

Originally Posted by ai-danno

I don't know if the system is finding confusion because they all answer on the same IRQ, or what.

PCI devices can share interrupts, not the problem.. but if you really think there are interrupt routing problems, try switching between apm+pcibios to ACPI. (or vice versa..)

http://en.wikipedia.org/wiki/Periphe...ect#Interrupts

Also, consider booting the GENERIC.MP kernel and doing the same thing.. it includes ioapic(4) support and will work fine (perhaps even better) even on UP systems.

[ai-danno]

Originally Posted by BSDfan666

Pretty simple stuff.. it's documented in both pccom(4), and com(4).

That's not true... what you replied with was nice, but that's not what is on those two man pages, which actually don't have a mapping of each of the ports. Also,we're talking about the ports on the serial card itself, not the ones included with the mobo, which neither you nor OBSD seems to list. I'm not 'complaining' about OBSD, just stating a problem I'm running into with it.

[BSDfan666]

I'm aware you were talking about PCI serial ports, my point is the driver and framework is the same.. the pccom/com(4) frameworks are used regardless of the attach point, so either com at isa? or com at puc? it doesn't matter.

If you look at pccom/com(4) you'll notice at the top that the first 4 numbers [0-3] are reserved for serial ports on the mainboard.. so counting starts at 4, the numbering is 1/1 with the device nodes.. so /dev/{tty,cua}04 would be pccom4/com4.

(An architecture can only use either the com(4) framework or the pccom(4) framework, not both.)

That's my rant for the day..