Testnet5

Testnet5 is a public test network defined by BIP 95, to replace testnet4. It runs mainnet consensus with none of the testnet exceptions: no minimum difficulty blocks, a higher minimum difficulty, and every soft fork, including the five rules of BIP 54, active from block 1.

Deployment status#

The genesis block, checkpoint and milestone below change when the testnet5 genesis block is mined, and a store made with the placeholder must then be made again.

Start the node on testnet5:

$ bs -n testnet5

-n testnet5 applies the built-in testnet5 defaults below, and keeps the store in a testnet5 directory under the working directory, apart from any mainnet store. Every run selects the network the same way. Without -n testnet5, bs uses the mainnet store.

The log files and the peer address cache (hosts.cache) are written by default to the working directory and are not separated by network, so run each network from its own working directory.

Defaults#

These are the settings in which the testnet5 defaults differ from mainnet, as displayed by bs -n testnet5 --settings. The derived bucket counts of the other tables also differ, as do the service ports (Ports).

[bitcoin]
network = testnet5
bip16_activation_time = 1329264000
bip34_activation_sample = 0
bip34_activation_threshold = 0
bip34_enforcement_threshold = 0
bip34_freeze = 0
bip54_coinbase_start = 4294967295
bip54_sigops_start = 4294967295
bip54_timespan_start = 4294967295
bip54_timewarp_start = 4294967295
bip54_txsize_start = 4294967295
bip65_freeze = 0
bip66_freeze = 0
bip9_activation_period = 0
bip9_bit0_start = 4294967295
bip9_bit0_threshold = 0
bip9_bit0_timeout = 0
bip9_bit1_start = 4294967295
bip9_bit1_threshold = 0
bip9_bit1_timeout = 0
bip9_bit2_activation_height = 0
bip9_bit2_speedy_trial = false
bip9_bit2_start = 4294967295
bip9_bit2_threshold = 0
bip9_bit2_timeout = 0
checkpoint = 000000000001bd3ade1e24d07c1a3677d4868c34f2f1696fa419e3b9f061b1e0:0
genesis_block = 00401c200000000000000000000000000000000000000000000000000000000000000000de48bbaa869592873fc4e5042f2931f9b42bb7e8ddeccd373df845d80983409b9663e96af8ff071b9916ba730101000000010000000000000000000000000000000000000000000000000000000000000000ffffffff5b04ffff001d01044c52323032362d31312d3033203937343334332030303030303030303030303030303030303030306138366436646132633135363364303836363864396563313863636535386362386338363564346133316338ffffffff0100f2052a010000000a6a089763e96a0000000000000000
milestone = 000000000001bd3ade1e24d07c1a3677d4868c34f2f1696fa419e3b9f061b1e0:0
minimum_work = 0000000000000000000000000000000000000000000000000000000000000000
proof_of_work_limit = 437256191

[peer]
identifier = 1163282758

[wallet]
hd_private_prefix = 70615956
hd_public_prefix = 70617039
p2kh_prefix = 111
p2sh_prefix = 196
silent_prefix = tsp
wif_prefix = 239
witness_prefix = tb

[inbound]
bind = 0.0.0.0:18353

[outbound]
connect_batch_size = 10
connections = 50

[node]
maximum_concurrency = 100000

[table.header]
expected = 156456
size = 17835984

[table.txs]
buckets = 150001
size = 604424

[table.tx]
expected = 14810011
size = 9478407

[table.ins]
expected = 33127580
size = 17226342

[table.outs]
expected = 57089349
size = 5138041

[table.input]
size = 87852864

[table.output]
size = 20343818

[table.candidate]
buckets = 150001

[table.confirmed]
buckets = 150001

[table.state]
buckets = 150001

[table.scan]
buckets = 150001

• [bitcoin] replaces the chain parameters, with soft forks active from block 1, and BIP 54 active without signaling.
• bitcoin.proof_of_work_limit is 0x1a0fffff, a higher minimum difficulty than mainnet's.
• peer.identifier is the testnet5 network magic (FIVE).
• [outbound] has no seeds, so the node finds no peers by itself. Name peers in [manual] (see Configuration).
• [wallet] sets the testnet address and key prefixes used by the server (Settings Reference).
• [table.*] sizes the store as for testnet4, at 150,000 blocks.
• node.maximum_concurrency raises the download window, since testnet blocks are small.

The [forks] settings are those of mainnet: forks.difficult = true (no minimum difficulty blocks), and forks.time_warp_patch and forks.block_storm_patch off, since BIP 54 replaces the testnet4 rules.

Configuration#

A configuration file is needed only to change a default. With no seeds, testnet5 needs at least one peer named in [manual]. The admin console and block explorer are off by default. This recommended file connects to a peer and serves both locally:

[bitcoin]
network = testnet5

[manual]
peer = <host>:18353

[admin]
bind = 127.0.0.1:58080
connections = 10

[native]
bind = 127.0.0.1:58180
connections = 10

Save it as testnet5.cfg and start the node with it:

$ bs -c testnet5.cfg

bitcoin.network in the file selects the network, so -n is not needed. The store is the same testnet5 store.

Ports#

On testnet5, each service listens by default on its mainnet port plus 50,000 (Conventional Ports):