Ethereum fast synchronization failed

1. A virtual currency with a wallet doesn't mean it's more professional and advanced. The existence of digital currency wallet is the premise of currency existence. Currency without wallet can be identified as fraud
mainstream digital currencies such as bitcoin, Puyin, Laite, Ethereum and dogcoin all exist in wallets, and wallets existed before the release of such currencies.

2.

what is Ethereum:

Ethereum is an innovation based on the application of technologies and concepts in bitcoin to computers. Ethereum itself imitates a lot of bitcoin technology to maintain the computer platform. blockchain technology is one of them
Ethereum platform can safely run any program users want

advantages of Ethereum over other competitive currencies before Ethereum appeared, some digital currencies imitated bitcoin. However, these projects have their own shortcomings, they can only support one or several specific applications at the same time< However, the reason why Ethereum can surpass the limitations of these projects in the past is because of the core idea of Ethereum

what Ethereum wants to implement is a blockchain protocol with built-in programming language. Since it supports programming language, in theory, any blockchain application can be defined with this language, and then run on Ethereum's blockchain protocol as an application

The design of Ethereum is very flexible and adaptable

Ethereum target sets the advantages of blockchain technology, in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields

blockchain applications of Ethereum

Ethereum has many blockchain applications, such as digital applications of gold and stocks, financial derivatives applications, DNS and digital authentication, etc

Ethereum has achieved more than 100 blockchain applications by many start-ups

Ethereum has also been closely watched by some financial institutions, banking consortia (such as R3), as well as large companies like Samsung, Deloitte, RWE and IBM. As a result, a number of blockchain applications such as simplified and automated financial transactions, merchant loyalty index tracking, and gift cards designed to achieve decentralization of electronic transactions have emerged

the relationship between Ethereum and blockchain:

Ethereum is a programmable blockchain

Ethereum does not give users a series of preset operations (such as bitcoin transaction), but allows users to create complex operations according to their own wishes

in this way, Ethereum can be used as a platform for various types of decentralized blockchain applications, including but not limited to cryptocurrency

like other blockchains, Ethereum also has a peer-to-peer network protocol. Ethereum blockchain database is maintained and updated by many nodes connected to the network. Each network node runs the Ethereum simulator and executes the same instructions. Therefore, people sometimes call Ethereum "world computer"

3. At the top of Ethereum is DAPP. It exchanges with the smart contract layer through Web3. JS. All smart contracts run on EVM (Ethereum virtual machine) and use RPC calls. Below EVM and RPC are the four core contents of Ethereum, including: blockchain, consensus algorithm, mining and network layer. Except DAPP, all other parts are in the Ethereum client. The most popular Ethereum client is geth (go Ethereum)

4. The cowhide wallet made by Zhang Zhenyue is very good. I want to make my own handiwork at home. If I don't pay attention to it, I'll buy 0.6cm thick cow leather, directly use ordinary large needles, and just wear more money to sew it

5. How to earn money by raising cats
on cryptokitties, you can buy virtual cats. By 17:00 Beijing time on December 6, 2017, the cheapest kitten had reached 0.037eth. Equivalent to 110 yuan per piece
then the kittens have some opinions about the generation. For example, Gen 12 indicates that it is the 12th generation, while Gen 20 indicates that it is the 20th generation. Generally speaking, the smaller the algebra, the more valuable it is. And you can make your kittens slap each other. For example, a Gen 1 kitten and a Gen 1 kitten will give birth to a Gen 2 kitten
you can sell your kittens and their offspring for money
but what if you don't have two kittens? If you only buy one kitten, you can use your kitten to have fun with other people's high-quality kittens. The fee also depends on the kittens (to be honest, this mechanism is very evil, similar to... Borrowing chickens to have children?) The quality of the proct. If your kitten is of high quality, you can also use your kitten to mate other people's kittens, and then you get Ethereum income
but kittens also have special fertility rates

every time a kitten gives birth to one generation, it will have a certain cooling time, and it can't regenerate kittens within the cooling time,
the cooling time is divided into several grades
fast: 1 minute
swift: 2 – 5 minutes
snappy: 10 – 30 minutes
brisk: 1 – 2 minutes
plodding: 4 – 8 minutes
slow: 16 – 24 minutes
sluggi Sh (lazy kitten): 2 – 4 days
catatonic (nervous kitten): 1 week
so the price of your cat also depends on its birth time
and generally speaking, the larger the algebra is, the higher the gen value is, and the slower their growth rate is
but I want to make complaints about it because CryptoKitties is too hot! Ethereum network has a little bit of a crash, the official recommended that every time you buy a cat, the minimum handling charge is 21000. 400000 fuel = 0.01eth. However, it is irritating that I raised the procere to 1.6 million fuel, which is 0.04, and Ethereum still failed. 0.04 Ethereum. That's more than 120 yuan. It's too dark.

6. How to earn money by raising cats
on cryptokitties, you can buy virtual cats. By 17:00 Beijing time on December 6, 2017, the cheapest kitten had reached 0.037eth. Equivalent to 110 yuan per piece
then the kittens have some opinions about the generation. For example, Gen 12 indicates that it is the 12th generation, while Gen 20 indicates that it is the 20th generation. Generally speaking, the smaller the algebra, the more valuable it is. And you can make your kittens slap each other. For example, a Gen 1 kitten and a Gen 1 kitten will give birth to a Gen 2 kitten
you can sell your kittens and their offspring for money
but what if you don't have two kittens? If you only buy one kitten, you can use your kitten to have fun with other people's high-quality kittens. The fee also depends on the kittens of your spouse (to be honest, this mechanism is very evil, similar to borrowing chickens to have children?) The quality of the proct. If your kitten is of high quality, you can also use your kitten to mate other people's kittens, and then you get Ethereum income
but kittens also have special fertility rates
every time a kitten gives birth to one generation, it will have a certain cooling time, ring which it can not regenerate kittens,
the cooling time is divided into several grades
fast: 1 minute
swift: 2 – 5 minutes
snappy: 10 – 30 minutes
brisk: 1 – 2 minutes
plodding: 4 – 8 minutes
slow: 16 – 24 minutes
sluggi Sh (lazy kitten): 2 – 4 days
catatonic (nervous kitten): 1 week
so the price of your cat also depends on its birth time
and generally speaking, the larger the algebra is, the higher the gen value is, and the slower their growth rate is
but I want to make complaints about it because CryptoKitties is too hot! Ethereum network has a little bit of a crash, the official recommended that every time you buy a cat, the minimum handling charge is 21000. 400000 fuel = 0.01eth. However, it is irritating that I raised the procere to 1.6 million fuel, which is 0.04, and Ethereum still failed. 0.04 Ethereum. That's more than 120 yuan. It's too dark.

7. Eth trunk interface is a kind of interface that can be created dynamically. This type of interface can be bound with several physical Ethernet interfaces as a logical interface. The Ethernet interface added to the ETH trunk interface is called the member interface. Users only need to configure the ETH trunk interface, and these configurations will eventually be mapped to the member interface. The ETH trunk interface can be divided into routing mode and switching mode. The routing mode Ethernet trunk interface is similar to the routing mode Ethernet interface, which can configure IP address, run various routing protocols, MPLS VPN and other services; The ETH trunk interface of switching mode is similar to Ethernet interface of switching mode, which can join VLAN, run STP and other protocols
the application features of eth trunk interface include expanding interface bandwidth, increasing link reliability and load sharing of traffic.

8. Yes, it can be used.

9.

Error reason:

Cisco has changed to CDP
version 2 after IOS
12.0 (3), and added VTP
management domainame and native
VLAN

The

full / half plex feature bits and the access
mode VLANs at both ends of the link are inconsistent, so the switch log will prompt native VLAN mismatch discovered

solution:

do not enable VTP
version 2, enter the command in global configuration mode:

switch? Sh CDP traffic

CDP counters:

total packets output: 26, input: 50

HDR syntax: 0, chksum error: 0, caps failed: 0

no memory: 0, invalid packet: 0, fragmented: 0

CDP version 1, advertisements output: 26, Input: 25

CDP version 2 advertisements output:0 ,
Input: 25

{rrrrrrr}

extended data:

Cisco common configuration command

1, enter a certain port of switch interface FastEthernet 0 / 17, take port 17 as an example

switch & gt; Enable

switch configure terminal

switch (CONF) ｛ interface FastEthernet 0 / 17

switch (CONF if) ｛

2. View the command show

switch & gt; Enable

switch # show version view all version information in the system

show interface VLAN 1 view switch related IP protocol configuration information

show running configure view switch current function configuration information

show interface FastEthernet 0 / 1 view switch 1 interface specific configuration and statistical information

show MAC address table view Mac Address table

3, switch restore factory default restore command

switch & gt; enable

switch# erase startup-configure

switch# reload

10. There is a conflict in the address. Check and change the IP address