, iPhone such as multi-touch and other design elements are obviously affected. As shown in the above figure, when ping 156 host, the PING command has not been responded to. It seems that our iptables rule has come into effect. The message sent by ping has not been accepted by 156 host at all, but has been discarded, so let alone any response. Well, we have successfully configured an iptables rule. It seems that we have already started.
Deep replication: After an object is replicated, both the basic data type and the reference type are recreated. In short, the deep copy has been completely and completely copied, while the shallow copy is not completely copied. Nat table: network address translation; Kernel Module: iptable_nat The first type is implemented through the relationship between the parent class and the child class. After releasing all the keys, the screen is completely black and enters DFU mode. At this time, opening itunes will prompt you to restore your mobile phone. If the time is not well controlled, it is recommended that the novice use the Red Snow tool to enter DFU mode, and can operate according to the prompts. Click Download Red Snow to open the Red Snow tool and select "Other". As shown in the figure, the iPhone screen will display the code to walk patiently and wait for the progress bar to finish during the operation according to the Chinese prompt. When the prompt is completed, the DFU mode has been successfully entered. As shown in the figure. Second, enter the detailed steps of recovery mode. (screen display icon) You can use the following command to load rules from the specified file. Note: When overloading rules, the rules in the file will overwrite the existing rules. The above example shows the deletion of a rule with a source address of 192.168. 1.146 and an action of DROP in the INPUT chain in the filter table. However, once again, when iptables rules are not saved, please do not empty the rules in the chain or table unless you understand what you are doing.
Which chains can use the rules in the table: PREROUTING, INPUT, FORWARD, OUTPUT, POSTROUTING The above example show that that default policy for the FORWARD chain in the filter table is set to ACCEPT
Iptables-save >/etc/sysconfig/iptables
Singleton is a common design pattern. In Java applications, a singleton object can ensure that only one instance of the object exists in a JVM. This model has several advantages:
REJECT: Reject the data packet from passing through, and when necessary, send a response message to the data sender. The client will receive the rejected message as soon as it requests. Let's take it apart. No.1 is the filter tip, No.2 PLA has shown signs of melting from this perspective, and No.3 hollow filter cotton also has traces of black edges. The last part of the smoke bomb was already quite dark. A message (usually a response message) is sent by a native process: OUTPUT--> POSTROUTING Rules for POSTROUTING can exist in: mangle table, nat table. 欧洲高清无卡码一区二区三区 The nat table in the following figure is no longer indicated in centos7. The original method! So let's explain the rules of iptables in a common way. There was an analogy before, Each "chain" is a "checkpoint", Every message passing through this "level" must match the rules on this level. If there is a match, The message is processed correspondingly, For example, you and I are like two "messages" at the moment. Both of you and I are going to enter the customs at this moment. But the duke has a life, Only the imposing person can enter the customs, Those who do not meet this requirement are not allowed to enter the customs. So the soldiers guarding the customs followed the "rules" formulated by the duke. I began to look at you and me. In the end, you entered the customs smoothly, and I was rejected. Because you met the standard of "dignity", you were "released", while I did not meet the standard, so I was not released. In fact, "dignity" is a kind of "matching condition", "release" is a kind of "action", and "matching condition" and "action" form the rules. The actual operation of iptables will be summarized into other articles. The direct link to the list of iptables series articles is as follows: People who join the IT industry are extremely intelligent, interested, creative, pragmatic and ambitious, with incomparable creativity, life and clear action goals. Quite a number of people already have humanities or business degrees and are looking for their ideals. They find that their current jobs lack challenges and development, so they decide to engage in high-challenge and high-income information industry through research. In the third step, if the iPhone is not a black screen but a LOGO is displayed on the screen, it means that DFU mode has not been successfully entered. It may be that you have pressed the key for too long, you can turn it off again, and then follow the above steps to enter again.
Which chains can use the rules in the filter table: INPUT, FORWARD, OUTPUT The biggest difference between the two is that the MAC OS system is not started in DFU mode, and itunes cannot decide whether the iPhone recovery process is interrupted, because the system is not started and related services cannot be enabled. It is said that the iPhone recovered in DFU mode is more thorough, and I have not compared it, so I will not make a conclusion here.
Let's think about another problem. We have placed a string of rules on each "chain", but some of these rules are very similar. For example, Class A rules filter IP or ports and Class B rules modify messages. At this time, can we put together the rules that realize the same function? We must be able to do so. However, once again, when iptables rules are not saved, please do not empty the rules in the chain or table unless you understand what you are doing. Here are the steps for configuring iptables-service in centos7 Now there is a rule in the INPUT chain that rejects all messages from the 192.168. 1.146 host. If we configure another rule after this rule, the latter rule stipulates that all messages from the 192.168. 1.146 host will be accepted, then will iptables accept messages from the 146 host? Let's try it. Modify the default policy (default action) of the specified chain of the specified table instead of modifying the rules, you can use the following command. In the last article, we have learned how to use the iptables command to view rules, so in this article we will summarize how to manage rules. It is an improvement on the common factory method mode. In the common factory method mode, if the passed string is wrong, the object cannot be created correctly, while multiple factory method modes provide multiple factory methods to create objects separately. Diagram: