Installing bitcoin and bitcoincash on same server
install Bitcoin ABC on Ubuntu 14.04.5 LTS, alongside Bitcoin Core, using these instructions:

Note: You have to create a new username because bitcoin and bitcoin cash use the same directory, so it won't work.


Download the appropriate binary from here: https://download.bitcoinabc.org/

For me, the command would be:

wget https://download.bitcoinabc.org/0.16.2/linux/bitcoin-abc-0.16.2-x86_64-linux-gnu.tar.gz
Extract the archive:

tar xzvf bitcoin-abc-0.16.2-x86_64-linux-gnu.tar.gz
Rename the binary files:

cd bitcoin-abc-0.16.2/bin/; rename 's/bitcoin/bitcoinCash/' *
Install the files into /usr/local/bin:

sudo install -m 0755 -o root -g root -t /usr/local/bin *


Finally!

bitcoinCashd -version outputs:


  Bitcoin ABC Daemon version v0.16.2.0-6af5e93
  
  [...]


bitcoind -version outputs:


  Bitcoin Core Daemon version v0.15.1
  
  [..]


ls /usr/local/bin outputs:

bitcoinCash-cli  bitcoinCash-seeder  bitcoind    test_bitcoin
bitcoinCashd     bitcoinCash-tx      bitcoin-qt  test_bitcoinCash
bitcoinCash-qt   bitcoin-cli         bitcoin-tx


Note: You have to edit the default port on bitcoin.conf file, Since Bitcoin-core and Bitcoin-cash will use the same RPC port. rpcport=4523