Baytech RPC3 Remote Power Controller – Serial Connection Issues

I purchased a Baytech RPC-3 Remote Power Controller from ebay and needed to set the IP information.  After reading the article from Altered Realms ( I was still having trouble connecting to the serial port.  After some studying of the user manual ( I realized that you need a “Rollover” RJ45 cable.  This is NOT a standard cross-over cable but luckily can be easily made by cutting a standard patch cable and twisting the following pairs together (1-8,2-7,3-6,4-5,5-4,6-3,7-2,8-1):

  • Light Orange / Brown
  • Orange / Light Brown
  • Light-Green / Green
  • Blue / Light-Blue
  • Light-Blue / Blue
  • Green / Light-Green
  • Light-Brown / Orange
  • Brown / Light-Orange


Once I hooked this up with the Female DB9 (9FRJ45PC-1) as per the image below…we were good to go.


The final connection should look like this:

[Baytech RJ45 management port] -> [Rollover RJ45 cable] -> [9FRJ45PC-1] -> [Serial port on PC (or USB to Serial Adapter)]

Troubles with FreeNAS and a ServeRAID M1015 cross flashed with LSI9211-8i in IT mode


For anyone looking to build a NAS device I highly recommend FreeNAS.  It has a variety of options but I was most interested in NFS/iSCSI for my Vmware ESXi lab.

I built a white box FreeNAS server and was having some troubles with my new M1015 SAS card.  I flashed it according to this post and I verified the firmware was correct (P16 as of the newest release).

For whatever reason the card would not recognize my drives that I had attached.  After an hour of troubleshooting I realized that there is a difference in breakout cables.  There are two types; reverse and forward cables.  You must purchase forward cables otherwise your drives will never be detected!  You can find a link to the correct cables below:



DDoS Attacks

I found the site Digital Attack Maps very informational (  Here is a live view of the current DDoS attacks in the US:

DDoS attacks have brought down many services in the past few weeks. They can be very complicated and can cause system administrators many stressful hours and long evenings of troubleshooting.

Adjusting the mouse pointer speed and acceleration in Chrome OS

You can adjust the trackpad/pointer settings via the GUI in Chrome OS, but I have found that the mouse speed still needs fine tuning.

Open a terminal window by pressing Ctrl+Alt+T.  At the crosh shell you can type the following command to see the usage of xset:

 xset m ?

The following output will be shown:

usage:  xset-mini option ...
    To set mouse acceleration and threshold:
         m [acc_mult[/acc_div] [thr]]    m default
    To turn auto-repeat off or on:
        -r [keycode]        r off
         r [keycode]        r on
         r rate [delay [rate]]

After playing with different settings, I have found the following command produces the most optimal feel and acceleration:

 xset m 0 0

Ubiquiti UniFi Access Points – Setting RSSI


Minimum RSSI works by kicking wireless clients that fall below the configured RSSI threshold. RSSI is a vendor-specific value. With UniFi, RSSI & SNR are synonymous. As long as a user remains above the RSSI threshold (SNR), they won’t be kicked.

If the Minimum RSSI value is 20dB, clients whose SNR drops to 19dB, 18dB, etc. will be kicked, allowing them to find a better access point.

This is very useful if you have multiple AP’s in a smaller location.  Sure, you can adjust the “power” of each access point, but I find this setting makes it easier to fix certain machines from holding to a connection that is losing signal strength.

To set this value for each Access Point you can follow the below steps:


Starting in v3.1.3, minimum RSSI configuration is done through file under each [UniFi base]/data/sites/the_site directory. The reason behind this decision is that (1) it is an advanced feature. (2) it requires a fine degree granularity of configuration down to each AP and each band, hence quite cumbersome if done in UI. A basic overview of the steps:

  1. In controller, create (or modify) file under each [UniFi base]/data/sites/the_site directory
  2. For each needed AP and band (n/g or n/a), add a mapping line in following format:
  3. config.minrssi.[AP MAC addr].[ng|na]=[Minimum RSSI value]

NOTE: There is NO:‘ nor ‘‘ in between MAC address bytes. [ng|na] means ‘ng’ OR ‘na’, ‘ng’ is 2.4 GHz band and ‘na’ is 5 GHz band.

Trigger a re-provision (NOT restart) to the AP. for example, enable/disable or disable/re-enable guest portal, changing TX power of an AP, etc. If you don’t want to re-provision entire network, you can only re-provision selected APs to make it effective on those APs.


1. SSH to UniFi controller and change directory to UAP site:

##SSH into UAP##
ssh ubnt@<unifi_controller_ip_address>
password: ubnt (default)

##Default path to UniFi default site##
Linux: /usr/lib/unifi/data/sites/default
Mac: /Applications/
PC: C:\Users\username\Ubiquiti UniFi\data\sites\default

2. When setting min RSSI for first time, you’ll likely need to create the file since it doesn’t exist yet. In this example, we’ll use a file editor likevi. Then add entries for each UAP under the given site (one entry per radio band). Then save the file and quit the editor.

##Create file or simply open using vi editor##
sudo vi

##add entries for dual-band UAP##

##Save and quit the editor##


3. SSH into UAP to check that minimum RSSI is set using ps command.

##SSH into UAP##
ssh ubnt@<uap_ip_address>
password: ubnt (default)

##Check processes##
830 ubnt      1568 S    /bin/stamgr -i 1 -b ng 20 -b na 20 -n 0