Tonight I needed to console into a old Cisco 2900 switch to test a couple password related items and it was the first time that I would be using USB to Serial adapter on my Macbook. Previously there had been a lot of issues with the adapter I have, which is a PL-2303, and getting the right drivers installed on Windows 7 64-bit so I was thinking there might not even be drivers available for OSX Lion. After a little research I cam across an article that purehate had written on QD however after following the instructions in the article the USB to Serial adapter still was not working. Below is information on installing newer drivers that will work on OSX Lion.
Alex and I were redoing our shop network today and we had to do some configuring on our Cisco switch. Normally this is no big deal but because I switched to mac recently I realized that I had no clue how to console into a Ciso switch. After a little googling I found a free program called zterm which people said would work. I use a proprietary program called Secure CRT which does console conections but if you do not have that check out zterm.
Anyway obviously there is no serial port on a macbook pro so I needed to use my usb to serial adapter. I plugged it in only to find that my mac did not “see” it as a device. As most Windows users, I was used to it comming up as a comm port so I was not sure where to look for it
I have had the same USB to serial adapter working on Windows XP for quite awhile. After I recently purchased a new laptop running Windows 7 64-Bit I needed to reinstall my USB to Serial Converter. I had a couple issues the first being the fact that the Dell Studio XPS laptop has a slot load CD/DVD drive and the drivers were on a mini CD. So the first thing I tried was to zip up the drivers CD that initially came with the USB to Serial Converter and get the zip file over to the new laptop. After doing this and attempting to install the drivers I was still receiving an error. I imagine either the drivers were not working with Windows 7 or there were no 64-bit drivers. Below I explain the USB error that was displaying, provide access to the correct drivers, and provide steps to install the drivers.
I have been asked the question numerous times of what PTS and TTY mean in Linux regarding terminals. People ask because they may be newer to Linux and learning how to view a process list they may actually see a serial connection, SSH connection, or a telnet connection in the process list that might show something like pts/0, pts/2, tty1, or tty2 in the TTY column. Most processes will just have a question mark in this column but if something is connected to an actual terminal then it will list where it is connected in the TTY column of “ps”.
When connecting to a Linux device using a serial port there may be times where that connection becomes stuck open and thus will not provide sane output to the TTY port. This issue can be resolved by killing the PID (Process ID) and letting the serial port process restart.
The serial port connection should be configured in inittab which will allow you to specify various configuration options as well as respawning the process. So when you specify respawn the process will automatically restart if it is no longer running as will be the case if you kill the process off. The inittab entry will look similar to one of the two below examples.