# Vocdoni Apex Chain
#### General
All nodes should take the docker image tagged as `release-apex` from the registry.
##### API
A single entrypoint for the API gateway.
+ https://apex.vocdoni.net
This is a very critical service, must have an SLA of 99%.
An idea would be to have multiple nodes behind this domain performing "sticky" load balancing.
```
VOCDONI_DATADIR=/app/run
VOCDONI_LOGLEVEL=info
VOCDONI_DEV=False
VOCDONI_CHAIN=apex
VOCDONI_ENABLEAPI=True
VOCDONI_ENABLERPC=False
VOCDONI_METRICS_ENABLED=True
VOCDONI_METRICS_REFRESHINTERVAL=5
VOCDONI_VOCHAIN_MEMPOOLSIZE=50000
```
##### Validators
A network of 9 validators, the blockchain supports 1/3 of failures, thus 3 validators might fail at same time and the network would still produce blocks.
+ each validator has a unique private key that must be in the ENV file.
```
VOCDONI_DATADIR=/app/run
VOCDONI_MODE=miner
VOCDONI_LOGLEVEL=info
VOCDONI_LOGERRORFILE=/app/run/dvote.err.log
VOCDONI_DEV=False
VOCDONI_VOCHAIN_LOGLEVEL=error
VOCDONI_VOCHAIN_MINERKEY=...secret...
VOCDONI_VOCHAIN_MEMPOOLSIZE=5000
VOCDONI_METRICS_ENABLED=True
VOCDONI_CHAIN=apex
VOCDONI_VOCHAIN_MINERTARGETBLOCKTIMESECONDS=10
```
min specs: 4 GiB ram, 40 GiB disk
##### Sentinels
These are nodes of the network, not producing new blocks but keeping a copy of the network and participating on the p2p network.
The sentinels must have a big mempool, so they can store pending transactions and transfer it to the validators slowly.
Around 5 sentinels should be fine.
min specs: 4 GiB ram, 40 GiB disk
```
VOCDONI_DATADIR=/app/run
VOCDONI_MODE=miner
VOCDONI_LOGLEVEL=info
VOCDONI_LOGERRORFILE=/app/run/dvote.err.log
VOCDONI_DEV=False
VOCDONI_VOCHAIN_LOGLEVEL=error
VOCDONI_VOCHAIN_MEMPOOLSIZE=50000
VOCDONI_METRICS_ENABLED=True
VOCDONI_CHAIN=apex
```
##### Seeds
Seeds are the nodes of the network that are used by other nodes for bootstraping. At least 2 seeds would be necessary.
```
VOCDONI_DATADIR=/app/run
VOCDONI_MODE=seed
VOCDONI_LOGLEVEL=info
VOCDONI_LOGERRORFILE=/app/run/dvote.err.log
VOCDONI_DEV=False
VOCDONI_VOCHAIN_LOGLEVEL=error
VOCDONI_VOCHAIN_MEMPOOLSIZE=5000
VOCDONI_METRICS_ENABLED=True
VOCDONI_CHAIN=apex
VOCDONI_VOCHAIN_NODEKEY=...secret...
```
min specs: 4 GiB ram, 40 GiB disk
##### Explorer
The explorer frontend needs to be deployed at https://apex.explorer.vote
It would be pointed to the API endpoint as backend https://apex.vocdoni.net/v2