Posts Tagged ‘USB’
Serial via USB in OS X
So I went to rebuild a Cisco router the other day, but didn’t have a freaking serial port anywhere to drop the config! So I ran down to Fry’s to get a USB-to-Serial adapter. Looking online there are several options, at the actual store I only had two/three to choose from. So I ended up with that ugly thing up above, mostly because even though I will PROBABLY never need dual rs232 ports, there might be that day that I need two (and it was only $1 more!). So that ugly thing up above is the USB-2925 from Cables Unlimited. The BIG problem is that according to their website (which contradicts the package) is that it only works on Mac OS 10.0-10.3! OUCH! But we can find a way around this, cause if not this write up would be worthless 
The USB-2925 uses the Moschip MCS7720, which has drivers for OS X. The only problem is the drivers are for 10.4, but they worked for me just fine in 10.6.2 (Snow Leopard). You do have to do the install followed by the restart, but after that take a look:
$ ls /dev/tty.* /dev/tty.Bluetooth-Modem /dev/tty.USB-Serial0.0 /dev/tty.Bluetooth-PDA-Sync /dev/tty.USB-Serial1.1
After that you can use the screen command to work with the connection as found in this guide.
Here is a copy of the drivers if you need them: MCS7720DRV_MAC10.X.zip
Installing ESXi 3.5 . . . half assed.
So the other day I started having weird problems with an ESX server that I had in my lab. Being that I don’t use it for anything too critical I decided to just put ESXi 3.5 (it is only 32-bit) on it. So I shutdown my VMs that were running, copied them off to my NAS, and put in the install CD to do the reinstall.
So the CD boots up, finds the SATA drive, and the install goes off just fine . . . so I thought.
About half way through the boot-up it starts looking for a USB drive and just freezes. Well I remember from a PaulDotCom episode that the hyper-visor is pretty small and it is handy to just boot from a USB stick.
So I went in search for this old Lexar 1GB drive that I knew I had sitting around here. Found it, then used the program to ‘switch the bit’ to make it look like non removable drive. I don’t remember all the original pages I used, but here is one that shows how easy it SHOULD be to do the install.
Well that didn’t work because the 3.5 install disk didn’t see my USB drive. So I moved back to the old method (posted here). Well that works like a charm, ESXi boots up and I start configuring the system and the network, then copy over the VMs from the NAS.
If only life was that easy though… I do an update on the ESXi server, reboot, and get this:
cannot get bank 1 parameters.
warning: bank 1 partition type invalid. Ignoring.
cannot get bank 2 parameters.
warning: bank 2 partition type invalid. Ignoring.
Panic: no usable banks found.
Well crap! So we have to reinstall and live without updates? I just got back from Shmoocon and saw a talk about stealing VMs, so this really doesn’t sit well with me. So I start the process over, but no matter what I do (partition, format, switch the bit back) nothing will boot on that drive again, and this is pre-update. So I start thinking . . .
Well I remember the HD install would freeze while looking for the stick, so the kernel was good to boot from SATA. And the USB drive shows information on it, but won’t boot, so the filesystem is good on there. See where I am going with this?
Well it worked, and the updates work and don’t kill it either. I installed from the CD to the SATA HD. Then I restored the image to the USB stick. Now the boot process starts up from the SATA HD, then moves over to using the filesystem from the USB drive. It all SEEMS to work ok. My only concern is the updates to the kernel. I am pretty sure those will not work because that is housed on the SATA drive, and the USB stick is what is getting updated. But for now, for what I am doing, this all makes me happy. . .
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