Ethereum broadcast time limit

1. Ethereum is registered in the United States

2. At present, their common point is blockchain + government affairs, but the application fields involve different scenarios. Personally, I don't think it's comparable. For the moment
according to the report, Zhejiang blockchain government platform is mainly engaged in blockchain bills, especially medical bills. The public platform of Changsha's SMIC blockchain mainly focuses on government information disclosure, government affairs handling, intellectual property protection, judicial expertise, finance and so on, but it has not involved the medical bills yet.

3. World of Warcraft mining skills level 1-375 alliance tribe complete upgrade route strategy

1-75: copper ore (smelting experience, can dig 1-4 times) is associated with poor quality stone and malachite
it's easy to dig in the birthplace, plus smelting experience, 50 + mining experience can be easily achieved

75-125: tin ore (smelting experience, can dig 1-4 times) 50 skill requirements, associated with tiger eye stone, shadow stone, rough stone
tin mine is also a very popular mineral. It is recommended by tribes to go to barren land / coniferous forest; The League recommends Chiji mountain

silver ore (smelting experience, can dig 1-4 times) 75 skill requirements, associated with tiger eye stone, rough stone
silver mine is the first rare mine we can encounter. Copper mine generates silver. That is to say, after a certain copper mine is collected, there is a certain chance to refresh silver mine next time. Of course, silver mine is also used as an independent refresh in advanced map. The tribe here recommends barren land / thousand needle stone forest; The League recommends Chiji mountain

125-175: iron ore (can be excavated 1-4 times) 125 skill requirements, accompanied by heavy stones and topaz
there are many places, but none of them is relatively distributed. However, I still suggest to go to the shining plain at the edge of the thousand needle Stone Forest - & gt; Tanalis, there's a lot of data going back and forth on this line

gold mine (smelting experience, 1-4 times of excavation) 155 skill requirements, accompanied by heavy stones and topaz
this is the second kind of rare ore that we can meet, and the last kind of ore with experience in smelting. Iron generates gold. Similarly, after the iron ore is collected, the next refresh will have a certain chance to refresh gold. Of course, the advanced map will refresh, but it is rare

175-245 mitag mine (can be excavated 1-4 times) 175 skill requirements, accompanied by solid stone, turquoise and ruby
two places are recommended for large-scale collection:
1. Barren land, as shown in Figure 1, will brush three secret silver in area a and two secret silver in area B. the refresh of these two places is very fast, and a circle of maps outside can't be finished, so areas a and B will refresh
2. If you think that there are too many people in the barren land, I recommend a small place, the altrank mountains, as shown in Figure 2. In the cave of area a, 2-3 secret silver will be refreshed each time, and in the refresh point outside, 3 mines will be brushed each time. This place has few people, and the map is small, and the refresh is relatively fast, which is suitable for a large number of collection
300-330, mainly to dig the magic iron ore

first of all, dig many magic iron ores distributed on Hellfire Peninsula clockwise

If Hellfire Peninsula is full of miners, go to ZANZA swamp

330-355, mainly for Moxian iron mine and Jiangang iron mine<

going to nagland grassland and digging hard steel ore can not only improve skills, but also sell ore at a good price

at the same time of digging hard steel ore, magic iron ore can also be collected together, even in the later stage, the consumption of magic iron ingot is still considerable

355-375, mainly for Moxian iron mine and Jiangang iron mine

yingyue gorge is the best choice for mining Jiangang mine

if the level is not enough, you can also choose to practice mining skills in the tiroka forest

don't forget to continue to search for magic iron ore while digging hard steel ore in yingyue canyon<

world of Warcraft mineral distribution

black coast: copper, tin, silver
damolo: Copper
lota: Copper
lockmodan: copper, tin
mogaorei: Copper
wetland: copper, tin, silver, iron
barren land: copper, tin, silver Iron ore
Irvine forest: Copper Mine
shizha mountain: copper mine, tin mine, silver mine, iron mine, Mithril
western wilderness: copper mine, tin mine, silver mine
ash Valley: copper mine, tin mine, silver mine, iron mine
Chiji mountain: copper mine, tin mine
thousand needle Stone Forest: copper mine, tin mine, silver mine, iron mine, Mithril
Twilight forest: copper mine, tin mine, iron mine Gold mine
desolate land: copper mine, tin mine, silver mine, iron mine, Mitsui, gold mine
tirisfalin: Copper Mine
st mud swamp: copper mine, tin mine, iron mine, gold mine, Mitsui
Yinsong forest: copper mine, tin mine, silver mine
tanalis: Iron Mine, gold mine, Mitsui, true silver, silver
Hillsbrad hills: copper mine, tin mine, silver mine Iron ore
Filas: iron ore, gold ore, Mithril, true silver, silver ore
altrank Mountains: copper ore, tin ore, iron ore, gold ore, silver ore
Isala: gold ore, Mithril, true silver, silver ore, silver ore
Arashi highland: tin ore, silver ore, iron ore, silver ore
fewood forest: gold ore, Mithril, true silver, silver ore
thorn Valley: tin ore, silver ore Iron ore, gold ore, Mitsui, true silver
angoro crater: gold ore, Mitsui, true silver, Se silver, Fu silver
barren land: silver ore, iron ore, gold ore, Mitsui, true silver
sirisus: Mitsui, true silver, Se silver, Fu silver
sad swamp: iron ore, Mitsui
Dongquan Valley: gold ore, Mitsui, true silver, Se silver Fuser silver
scorching gorge: iron ore, Mithril, Mithril, black iron
tedasher: there are no ore occurrences at present
singland: silver ore, iron ore, gold ore, Mithril, true silver, sethril
moonlight woodland: there are no ore occurrences at present
land of curse: gold ore, Mithril, true silver, sethril
Burning Plain: gold ore, Mithril, true silver, black iron, sethril Fuseyin
West plague land: gold mine, secret silver, true silver, Se silver, fuseyin
East plague land: gold mine, secret silver, true silver, Se silver Fuser silver

after 375
375-400
cobalt ore: howling wind fjord Grizzly Bear Hill Northwind tundra keel wilderness
400-430
saloon ore: gudake sulasa basin
430-450
Titan ingot: Storm cliff ice cap glacier

5. Fund stock and virtual currency are totally different concepts. Compared with fund, fund is the simplest. You only need to understand the history of fund managers and profit management companies. You can find some well-known large funds that are relatively standardized. Generally, the risk is not too big, but you don't have to expect too high returns. After all, the scale of the fund is large, It must be the first factor of safety.
compared with funds, stocks are more risky. After all, stocks fluctuate a lot. There are thousands of stocks. Even if the index rises, the stocks you buy may fall instead. Of course, the stocks you buy are much stronger than the index.
virtual currency is another concept. A few years ago, virtual currency was quite popular, However, since September 2017, the people's Bank of China, China Banking Regulatory Commission, China Securities Regulatory Commission, China Insurance Regulatory Commission, State Administration for Instry and commerce, etc. have jointly issued an announcement on preventing the financing risk of token issuance. As a result, the virtual currency has been comprehensively rectified. The virtual currency can no longer be exchanged in China, and all transactions are overseas, The risk is uncontrollable
the relevant information can be obtained through network query
personal opinion, for reference only

6. The first method is to use grep and cut values
the second method is to use grep and awk (the default separator is the space) values
the third method is to use grep and awk (multiple separators)
the fourth method is to use sed and awk
the fifth method is to use grep and awk (multiple separators and plus sign +)
the sixth method is to use awk (separators and their values) Line)
the seventh method: grep network card file
the eighth method: head line awk segmentation

if you don't understand anything, you can read the book "this is how to learn Linux", which is very suitable for novices to learn Linux.

7. Now we are all concerned about Ethereum. How to trade Ethereum? I think we all want to know something, so let's make it up here to introce a lot of content about how to trade ether currency? The most intuitive explanation of Ethereum's transaction is the message and signed packet sent from an external account to another account on the blockchain<

contains the following contents:
sender's signature
receiving address
number of transferred digital currency, etc.
transactions on Ethereum need to pay fees, which is different from bitcoin. Ethereum has fixed this link, so this indirect understanding is a security error of Ethereum, It can prevent a large number of meaningless transactions and ensure a certain degree of security. In particular, the creation, execution and call of smart contracts need to consume costs, so it can also ensure the stability of the whole system and prevent some meaningless malicious behaviors on the chain
transaction handling fee
the core of Ethereum is EVM, Ethereum virtual machine, so the bytecode executed in EVM has to pay for it. That is, we often see the concepts of gas, gas limit and gas price
gas: literally, it means gasoline. Ethereum needs gas to run just like everyday cars. Gas is the basic unit for calculating consumption in a transaction. There is a list to intuitively see the gas consumption of operation in Ethereum:
the specific content of gas consumption of operation
the default cost of step 1 execution cycle
stop0 termination is free
suicide0 is the internal data storage space of the smart contract account. When the contract account calls the suicide() method, the value will be set to null<
sha320 encrypts and decrypts
sload20 obtains
sstore100 in the fixed memory and inputs it into the fixed memory
balance 20 account balance
create100 creates a contract
call20 initializes a read-only call
additional cost paid for memory expansion
consumption of each byte of data or code in txdata5 transaction process
transaction 500 transaction At present, the cost of contract creation 53000 homestead is adjusted from 21000 to 53000
so some companies or indivials feel that blockchain technology is disintermediated and does not need a central server. This development mode is relatively cheap, but in fact, the development of blockchain is not cheaper than those of traditional software development before
gas price: literally, it's like going to a gas station, what's the price of gasoline today. A gas price is the unit price, so your transaction cost = gas * gas price, and then you pay in ether. Of course, you think I don't want to pay fees. You can set gas price to 0, but the choice is in the hands of miners, and miners have the right to choose to accept transactions and charge fees. The simplest way to think about it is very difficult for a miner to accept a transaction with a very low price. In addition, the default gas price of Ethereum is 1wei
gas limit: literally, it is the limitation of gas. Limitation is necessary. Without limitation, there will be no constraint. This gas limit has two meanings. First of all, for a single transaction, this indicates how much gas the initiator of the transaction is willing to pay at most. The initiator of the transaction needs to set it when initiating the transaction. There is also a gas limit for blocks. A single block also has a gas limit
suppose several scenarios to illustrate the use of gas:
if the user sets the gas limit, then in the transaction process, if your actual consumed gas is used
if the user sets the gas limit, then in the transaction process, if your actual consumed gas is used & gt; Gas limit, then the miner must find that your gas is insufficient, and the transaction cannot be executed. After that, the transaction will be rolled back to the state before execution. At this time, the miner will charge gas price * gas limit
the gas limit of the block. There is a gas upper limit in the block, and different gas limits specified by the user will appear in the received transactions. Then the miners will choose according to the gas limit of the block limit and "reasonably" choose the packaged transaction
specific transaction
the transaction on Ethereum can be a simple transfer of Ethernet currency, and it can also be a code message of smart contract. List a table to see the specific content of the transaction:
code content
from the address of the transaction initiator, cannot be empty, and the source is not unreasonable
to the address of the transaction receiver (this can be empty, which means the creation of a contract)
value the number of Ethernet coins transferred
data field. When this field exists, it means that a transaction is a transaction that creates or invokes a smart contract.
gas limit literally means the limit of gas. The limit is necessary. If there is no limit, there will be no constraint. This gas limit has two meanings. First of all, for a single transaction, this indicates how much gas the initiator of the transaction is willing to pay at most. The initiator of the transaction needs to set it when initiating the transaction. There is also a gas limit for blocks. A single block also has a gas limit
gas price a gas price is the unit price, then your transaction cost = gas * gas price, and then you pay in ether. The default gas price of Ethereum is 1wei
nonce is used to distinguish the identity of the transaction issued by the user
hash transaction ID is a hash value generated from the above information, which is the three parts of
R, s and V transaction signature. The private key of the transaction initiator generates the hash signature
there are three types of transactions
transfer: simple and clear transfer of Ethernet currency on Ethereum, similar to bitcoin, a transfers a certain amount of Ethernet currency to B. This kind of transaction includes: the number of initiator, receiver and value of the transaction, and others like gas limit, hash and nonce will be generated by default. So you will see a piece of code:
Web3. Eth. Sendtransaction ({from: & quot; Address of transaction originator;, To: "address of transaction receiver", value: quantity})
smart contract creation: to create a smart contract is to deploy the smart contract to the blockchain, then to is an empty field at this time. The data field is the code to initialize the contract. So you can see the code:
Web3. Eth. Sendtransaction ({from: & quot; Address of transaction originator;, data: " contract binary code"});
smart contract execution: if the contract is created and deployed on the blockchain, the execution will add the to field to the address where the smart contract is to be executed, and then the data field will be used to specify the transfer of methods and parameters to be called, so you can see the code:
Web3. Eth. Sendtransaction ({from: & quot; Address of transaction originator;, To: "address of contract executor", data: "transfer of called methods and parameters"})
the above are roughly the types of transactions
transaction confirmation
like bitcoin, Ethereum transaction can only be confirmed after subsequent block confirmation and node synchronization. The simple understanding is to dig out more blocks and confirm the transaction after verification. Ethereum often has congestion, so sometimes it needs to wait for confirmation
transfer and contract transaction flow
first, transaction initiator a initiates a transfer transaction, Then the sending format is as follows:
code details
from the address of the transaction initiator
to the address of the transaction receiver
value the number of Ethernet coins transferred
the amount of gasgas
the unit price of gas pricegas
data the message sent to the receiver
nonce transaction number
node verification: a node in Ethereum network will receive the message sent by A, Then check whether the message format is valid, and calculate the gas limit. At this time, go back to verify a's Ethereum balance. If the balance is insufficient, an error will be returned and will not be processed. Once the message sent by a passes the verification of the node, the node will put the transaction into the transaction storage pool. And broadcast to the blockchain network
miner verification: the miner must package when writing to the blockchain. When the miner receives the transaction sent by a, it will package together with other transactions, and the ordinary transfer transaction can be packaged. Then the transaction called by the contract needs to execute the calling contract code on the miner's local EVM, and the gas consumption is checked ring the code execution. Once the gas is consumed, it will be rolled back. If the gas is enough, the extra gas will be returned. And broadcast to the blockchain network
other nodes: repeat the node verification steps, and then the contract will also perform verification on the local EVM. Synchronize the blockchain after verification
first, initiator a initiates a transaction request to create a smart contract. The format is as follows:
code details
address of the transaction initiator
to0
value number of Ethernet coins transferred
quantity of gasgas
unit price of gas pricegas
data contract code
nonce transaction number
node verification:
a node in Ethereum network will receive the message sent by a to check whether the transaction is valid and whether the format is correct, Verify the transaction signature. Calculate gas, determine the address of the originator, and then query the balance of ether currency in account a. If the balance is insufficient, an error will be returned and will not be processed. Once the message sent by a passes the verification of the node, the node will put the transaction into the transaction storage pool. And broadcast to the blockchain network
miner verification:
if the miner packages the transaction, the contract account will be created according to the transaction cost and contract code, and the contract will be deployed in the account space. Here we say the contract address (the address of the smart contract account has the address of the initiator and the random number of the transaction as the input, and then generated by the encryption algorithm). After the transaction is confirmed, the address of the smart contract will be returned to a. And broadcast to the blockchain network
other nodes:
repeat the node verification steps, verify the block, update a's smart contract transaction in the node's memory pool, synchronize the blockchain, and deploy the smart contract in its own local blockchain.

8. The configuration of the first network card in Linux system
description of ifcfg-eth0 configuration parameters in Linux:
ifcfg-eth0 is in / etc / sysconfig / network scripts,
its configuration is as follows:
device = physical device name
IPADDR = IP address
netmask = mask value
Network = network address
broadcast = broadcast address
gateway = gateway address
onboot = [yes | no]
userctl = [yes | no] (whether non root users can control the device)
bootproto = [none | static | BOOTP | DHCP] (boot) No protocol | static allocation | BOOTP protocol | DHCP protocol)
hwaddr = MAC address
some parameters are not required
the original configuration is as follows:
device = eth0
bootproto = DHCP
onboot = yes
in this case, the NIC is not activated
the modified configuration is as follows:
device = eth0
bootproto = static
broadcast = 192.168.129.128
IPADDR = 192.168.129.2
netmask = 255.255.255.0
Network = 192.168.129.0
onboot = yes
in this way, the network card can be activated every time it is turned on.

9. You can try to change ifcfg-eth0 under / etc / sysconfig / network script / to ifcfg-front1. You haven't done the similar operation you said before. It's recommended that you do it from the testing machine to avoid causing failure. Eth0 should be the default network card name.

10. Does it take a long time to show failure? It should be that you set eth0 to obtain IP in the way of DHCP, and there is no DHCP server in your network, so you will wait for a long time to pass. Check whether the DHCP in VMware is enabled in the service, and the NAT service can also be set to manual
device = eth0 # to describe the device alias corresponding to the network card, For example, in the ifcfg-eth0 file, it sets the method of obtaining IP address for eth0
bootproto = static #. The possible options are static, DHCP or BOOTP, which correspond to the static IP address and the IP address obtained through the DHCP protocol, IP address obtained through BOOTP protocol
broadcast = 192.168.0.255 ｛ corresponding subnet broadcast address
hwaddr = 00:07: e9:05: E8: B4 ｛ corresponding NIC physical address
IPADDR = 12.168.1.2 ｛ if the IP address obtained by NIC is statically specified, this field specifies the IP address corresponding to NIC
ipv6init = no
IPv6_ Autoconf = no
netmask = 255.255.255.0 ｛ network mask corresponding to network card
Network = 192.168.1.0 ｛ network address corresponding to network card
onboot = yes ｛ whether this network interface is set when the system starts up; when it is set to yes, this device is activated when the system starts up