Recently I attempted to get a mid server running on my raspberry pi and could find no clear instructions. Here is what I did to get it working on a Pi 3 model B running respian jessie light, hopefully it can help you out in your efforts.

1. 1. As the JRE the mid server comes with does not work on the arm archectature, you must install the ARM version of JRE
   1. sudo apt-get install openjdk-8-jre-headless
   
   1. Create destination for your mid server files
      
      1. sudo mkdir /servicenow
         
      2. cd /servicenow
         
   2. Figure out what mid server you need.
      
      1. from your instance, navigate to Mid Server > Downloads in the left nav
         
      2. right click 32 bit under linux, and copy URL / Link Address
         
   3. Download mid server files into your servicenow directory
      
   4. Unzip your files. From here we will be modifying the /servicenow/agent directory to change things to work on the pie. Once this is done, the /servicenow/agent directory will be used to copy to each mid server you need
      
      1. sudo unzip mid.[press tab to auto complete]
         
   5. Figure out your exact processor architecture. Run the command and review the highlighted line
      
      • uname -a
        pi@urchpi01:/servicenow $ uname -a
        Linux urchpi01 4.4.34-v7+ #930 SMP Wed Nov 23 15:20:41 GMT 2016 armv7l GNU/Linux
        
      • NOTE! The last character in the above example is a lowercase letter L !!
        
   6. Setup the wrapper files matching your pi's architecture
      
      • If your architecture is armv7l, setup symlink to existing wrapper:
        
      • * sudo ln -s -r /servicenow/agent/bin/wrapper-linux-arm-32 /servicenow/agent/bin/wrapper-linux-armv7l-32
        
      • If your architecture is armhf, download the attached armv6l.zip file, and place the files in the following locations:(Thanks to Lance D'Souza for noting this)
        
      • * /servicenow/agent/lib/libwrapper-linux-armhf-32.so
        * /servicenow/agent/bin/wrapper-linux-armhf-32
        
   7. Edit wrapper override configuration to point to external JRE and change max memory
      
      1. 1. sudo nano /servicenow/agent/conf/wrapper-override.conf
         2. Under External JRE uncomment the line for wrapper.java.command and update to the following
         * wrapper.java.command=/usr/lib/jvm/java-1.8.0-openjdk-armhf/jre/bin/java
         3. Under System resources uncomment wrapper.java.maxmemory, and set to a value that makes since for your Pi. My Pi has 1gb of memory, and I plan on running 2 mid servers so I chose 256 mb. I have been running it solid for a few days now without issue.
         4. [Ctrl + x] exits, select [Y] save, enter for current file location
         
   8. Edit the wrapper file to correct the processor architecture (Thanks to Robert Beeman for noting this)
      
      1. sudo nano /servicenow/agent/conf/wrapper-jvm.conf
         
      2. change set.SNC_JVM_ARCH=x86-32 to set.SNC_JVM_ARCH=arm
         
   9. Now copy the folder for your mid server and copy the agent into it
      
      1. Setup the directory and move mid into it
         1. sudo mkdir [your_mid_server]
         2. sudo cp -r /servicenow/agent/ /servicenow/[your_mid_server]/agent/
         3. cd [your_mid_server]/agent/
         
      2. Config your mid server
         1. sudo nano ./config.xml
         2. Edit file as normal
         3. [Ctrl + x] exits, select [Y] save, enter for current file location
         
      3. Start it up / test it out
         
   10. You can use cron to automatically start your mid server when the pi boots
       
       1. sudo crontab -e
          
       2. Add these lines to the bottom of the cron file. First I delete the old logs so the current log remains agent0.log, then I start the mid. I cd first because from what I can tell some of the paths in the start script are relative and break if you don't start form the correct directory.
          1. @reboot sleep 10 && rm -r /servicenow/[your_mid_server]/agent/logs/*
          2. @reboot sleep 11 && cd /servicenow/[your_mid_server]/agent && ./start.sh
          3. [Ctrl + x] exits, select [Y] save, enter for current file location

Repeat step 10 and 11 for multiple mid servers

Troubleshooting

1. 1. "Unable to locate any of the following binaries:"
   * This message occurs when there is not a wrapper file that matches your processor architecture.
   * Review the binaries that are supposedly missing and create symlinks to those specific names similar to step 7 above.
   * Remember in my examples, the last highlighted character is a lowercase L NOT a number 1.
   
   1. Review logs/wrapper.log
      
      1. If you see error messages for missing files, create symlinks from the existing ...arm... file to the missing file similar to step 7
         * I had these symlinks in a earler version of this document, but thought them unnecessary. If you are having problems, try adding these symlinks back in. Be sure to add them to each mid instance's directory:
         * sudo ln -s -r /servicenow/agent/lib/libwrapper-linux-armhf-32.so /servicenow/agent/lib/libwrapper-linux-null-32.so
         * sudo ln -s -r /servicenow/agent/bin/wrapper-linux-arm-32 /servicenow/agent/bin/wrapper-linux-armv7l-
         
      2. If you see error messages for mismatch versions:
         1. Review available jre versions
         1. sudo apt-cache search jre
         2. Review installed jre versions
         3. Go back to step 8, and try the different JRE versions.
         
   2. Wifi can be difficult to get up and running for those of us not familiar on linux command line. Here is the guide that helped me get wifi running: Setting WiFi up via the command line - Raspberry Pi Documentation. You should only need to configure the /etc/wpa_supplicant/wpa_supplicant.conf file.