Installing Ethereum on a VPS
on the smallest VPS you may only get 512mb memory, this is a big issue for geth without a big swap file.
This weekend I am going to install the Ethereum Go Client, it will allow me to do a little bit of Ether mining and more importantly act as a node that I can connect to via the web3.js library on the client. Diving right in…
make a new droplet and attach a volume of at least 6GB. The initial download/sync up will be about 3.8GB as of April 2017. I called mine “eth-blockchain” as you will see further down, so be sure to name it the same or change the name if you are following along.
Follow the instructions for mounting the drive and increase the swap size and re boot
fallocate -l 2G /swapfile
chmod 600 /swapfile
mkswap /swapfile
sudo swapon /swapfile
reboot
check the file and permissions
ls -lh /swapfile
and you should see somthing like
-rw------- 1 root root 2.0G Apr 8 01:58 /swapfile
and check the swap is on
sudo swapon -s
let’s make this change permanent
sudo nano /etc/fstab
and enter this line at the bottom
/swapfile none swap sw 0 0
set the swappiness and cache pressure
sudo nano /etc/sysctl.conf
enter these lines at the end
vm.swappiness=10
vm.vfs_cache_pressure = 50
Install geth
apt-get install software-properties-common
add-apt-repository -y ppa:ethereum/ethereum
apt-get update
apt-get install geth
Start the console
geth attach ipc:/mnt/eth-blockchain/geth.ipc
and start up the RPC
admin.startRPC("127.0.0.1", 8545, "*", "web3,db,net,eth")
Now we can exit the console by typing “exit”.
we need geth to start on reboot..
nano /lib/systemd/system/geth.service
Copy in
[Unit]
Description=Ethereum Go Client
[Service]
ExecStart=/usr/bin/geth --fast --cache=16 --datadir=/mnt/eth-blockchain --identity=@bkawk --keystore=/mnt/eth-blockchain --rpc --rpcport=8882 --rpccorsdomain=* --rpcapi=web3,db,net,eth
Restart=always
RestartSec=30
Type=simple
User=root
Group=root
[Install]
WantedBy=multi-user.target
and Ctrl + X to save it and then reload it with:
systemctl daemon-reload
systemctl enable geth.service
Start it up and let’s have a look and see what magic happened
reboot
journalctl -u geth -n20
Now walk away, dont tweak around , dont restart, reboot, resize, just let it run.
Geth console
Are we done already?
geth attach ipc:/mnt/eth-blockchain/geth.ipc
start RPC
admin.startRPC("127.0.0.1", 8882, "*", "web3,db,net,eth")
get the complete status
geth.syncing
for a % done past in the below
setInterval(function(){var s = eth.syncing; console.log("%"+( s.currentBlock/s.highestBlock*100).toFixed(3)) }, 1000);
The sync will start fast and then slow down a bit towards the end.
From time to time you can check the block number which is the one after the # symbol when issuing
journalctl -u geth -n40
Once we are up to date it’s important to remove the fast flag
nano /lib/systemd/system/geth.service
and remove the
--fast
restart and check all is good
reboot
journalctl -u geth -n40
Time to mine?
Whether it's just to feel good that you are contributing or if having a chance to win the jackpot, mining can be setup quickly, its interesting but not practical, so feel free to skip it.
Once the node is all synced-up, make a new account.
geth account new
enter a password twice, make a note of the account
0d4c318aded3d9933256e0e83021227b82bc7f91
unlock the account
geth account update 0d4c318aded3d9933256e0e83021227b82bc7f91
enter the password and then enter a new password twice and again edit the service
nano /lib/systemd/system/geth.service
and copy in
[Unit]
Description=Ethereum Go Client
[Service]
ExecStart=/usr/bin/geth --cache=16 --datadir=/mnt/eth-blockchain --identity=@bkawk --keystore=/mnt/eth-blockchain --rpc --rpcport=8882 --rpccorsdomain=https://bkawk.com --mine --minerthreads=1 --etherbase=0d4c318aded3d9933256e0e83021227b82bc7f91
Restart=always
RestartSec=30
Type=simple
User=root
Group=root
[Install]
WantedBy=multi-user.target
and Ctrl + X to save it and then reload it with:
systemctl daemon-reload
systemctl enable geth.service
Start it up and let’s have a look and see what magic happened
systemctl start geth
journalctl -u geth -n20
Follow the logs
journalctl -u geth -f
Backup the keystore
change directory to
cd /root/.ethereum/keystore
and change locally to
lcd /Users/will/Desktop/
get the file
get /root/.ethereum/keystore/UTC--2017-04-08T14-13-40.418444512Z--3ff341f6248e36c576ef0dba3db3f36e251af9b3
You can now import wallet this into Meta Mask or whatever you like and see the mining money flow in! Well it’s not going to flow in, you are solo mining on the CPU of a not so powerful mache, this is like waiting for the jackpot, if you are lucky enough to find a block you will get a full block reward of 5 Ether, about 240 usd at today’s rates, expect to wait months if not years.
if you want to throw in the cards at this point just edit
nano /lib/systemd/system/geth.service
by removing
--mine --minerthreads=1 --etherbase=0d4c318aded3d9933256e0e83021227b82bc7f91
then delete the DAG’s found here
rm -fr ~/.ethash
Restart!
systemctl daemon-reload
systemctl start geth
Point an A record
It looks nice when a Geth’s RPC port has an address so point the A record at the server's IP address.
Even though we limited the RPC CORS domain to https://www.bkawk.com, for anything more than just testing you will need some added protection from nginx…
apt-get install nginx
setup a site
nano /etc/nginx/conf.d/eth.bkawk.com.conf
copy in the below
Notice the port is 8882, the same port we set in geth.service for the rpc port.
server {
listen 80;
server_name eth.bkawk.com;
location / {
proxy_pass http://localhost:8545;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_set_header Host $host;
proxy_cache_bypass $http_upgrade;
}
}
check there is no errors
sudo nginx -t
restart nginx
sudo systemctl restart nginx
wait for the domain to propagate
We can now connect to this node directly from the browser using the wb3 javascript library or have a little express API requests from the client and pass them to geth, this gives you the option to keep geth away from the public and allows you full control through an API.
