For tutorial: https://steemit.com/witness/@ety001/how-to-deploy-a-steem-witness-node-by-docker

config_witness.ini

# Endpoint for P2P node to listen on
p2p-endpoint = 0.0.0.0:2001

# Maxmimum number of incoming connections on P2P endpoint
p2p-max-connections = 200

# Shared file size
shared-file-size = 64G
#shared-file-dir = /shm/

# A 2-precision percentage (0-10000) that defines the threshold for when to 
# autoscale the shared memory file. Setting this to 0 disables autoscaling. 
# The recommended value for consensus node is 9500 (95%). Full node is 9900 (99%).
shared-file-full-threshold = 9500

# A 2-precision percentage (0-10000) that defines how quickly to scale the shared memory file. 
# When autoscaling occurs, the file's size will be increased by this percentage. 
# Setting this to 0 disables autoscaling. The recommended value is between 1000 and 2000 (10-20%).
shared-file-scale-rate = 1000

# Target blocks to flush
flush = 100000

# P2P nodes to connect to on startup (may specify multiple times)
p2p-seed-node = seed-east.steemit.com:2001 # steemit
p2p-seed-node = seed-central.steemit.com:2001 # steemit
p2p-seed-node = seed-west.steemit.com:2001 # steemit
p2p-seed-node = sn1.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = sn2.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = sn3.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = sn4.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = sn5.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = sn6.steemit.com:2001 # Steemit, Inc.
p2p-seed-node = seed.justyy.com:2001 # @justyy
p2p-seed-node = steem-seed.urbanpedia.com:2001 # @fuli
p2p-seed-node = seed.steem.fans:2001 # @ety001
p2p-seed-node = seed-1.blockbrothers.io:2001 # @blockbrothers
p2p-seed-node = 5.189.136.20:2001 # @maiyude
p2p-seed-node = seed.steemhunt.com:2001 # @steemhunt Location: South Korea
p2p-seed-node = seed.steemzzang.com:2001 # @zzan.witnesses
p2p-seed-node = seednode.dlike.io:2001 # @dlike Location Germany
p2p-seed-node = seed.steemer.app:2001 # @bukio
p2p-seed-node = seed.supporter.dev:2001 # @dev.supporters
p2p-seed-node = seed.goodhello.net:2001 # @helloworld.wit


# Pairs of [BLOCK_NUM,BLOCK_ID] that should be enforced as checkpoints.
# checkpoint =

# Endpoint for websocket RPC to listen on

#webserver-http-endpoint = 0.0.0.0:8091
#webserver-ws-endpoint = 0.0.0.0:8090

# Endpoint for TLS websocket RPC to listen on
# rpc-tls-endpoint =

# The TLS certificate file for this server
# server-pem =

# Password for this certificate
# server-pem-password =

# Block signing key to use for init witnesses, overrides genesis file
# dbg-init-key =

# API user specification, may be specified multiple times
# api-user =

# Plugin(s) to enable, may be specified multiple times
# plugin = witness condenser_api network_broadcast_api account_by_key database_api
plugin = witness

# Defines a range of accounts to track as a json pair ["from","to"] [from,to)
# track-account-range =

# RPC endpoint of a trusted validating node (required)
# trusted-node =

# Track market history by grouping orders into buckets of equal size measured in seconds specified as a JSON array of numbers
bucket-size = [15,60,300,3600,86400]

# How far back in time to track history for each bucket size, measured in the number of buckets (default: 5760)
history-per-size = 5760

# Defines a range of accounts to private messages to/from as a json pair ["from","to"] [from,to)
# pm-account-range =

# Enable block production, even if the chain is stale.
enable-stale-production = false

# Percent of witnesses (0-99) that must be participating in order to produce blocks
required-participation = 33

# name of witness controlled by this node (e.g. initwitness )
# witness =

# WIF PRIVATE KEY to be used by one or more witnesses or miners
# private-key =

# name of miner and its private key (e.g. ["account","WIF PRIVATE KEY"] )
# miner =

# Number of threads to use for proof of work mining
# mining-threads =

# Account creation fee to be voted on upon successful POW - Minimum fee is 100.000 STEEM (written as 100000)
# miner-account-creation-fee =

# Maximum block size (in bytes) to be voted on upon successful POW - Max block size must be between 128 KB and 750 MB
# miner-maximum-block-size =

# SBD interest rate to be vote on upon successful POW - Default interest rate is 10% (written as 1000)
# miner-sbd-interest-rate =

# Console appender definition json: {"appender", "stream"}
log-appender = {"appender":"stderr","stream":"std_error"}

# File appender definition json:  {"appender", "file"}
log-appender = {"appender":"p2p","file":"logs/p2p/p2p.log"}

# Logger definition json: {"name", "level", "appender"}
log-logger = {"name":"default","level":"debug","appender":"stderr"}
log-logger = {"name":"p2p","level":"warn","appender":"p2p"}