network packet broker

protocol implemented here for detecting host 172.40.50.123 80 ports and 172.40.50.148 we can use () to raise or priority to implement 80 ports listening on two hosts () cannot be recognized by the system command, we need to use \ backslash to fetch Eliminate its definitionNMAP-A-i eth0 TCP port and \ (host 172.40.50.123 or host 172.40.50.148\)Here is a simple script, using the location variable, where the shift to skip the previous definition, so our port port is not entered into the definition

port to enable ACL policyNetwork topology1, configure Router 1, turn on the single-arm routing configuration subinterface address and connect the physical interface address of another route and open the port2 Configuring the VLAN of the switch, configuring the port type3 Configuring the IP address of the PC, specifying the gateway4 Configuring router static routing to enable network interoperability5 Create a new ACL policy on the destination router6

server can not stand the client's endless keepalive request, to release a connection. Judging from the data, the entire four waves are time consuming, 166.387505-166.162996 = 0.224509OK from here, it can be seen that the entire HTTP request process one go, very fast, almost in less than two seconds to complete the entire data request, as for UI drawing in milliseconds, so you can see at the code level regardless of the server or the client has no performance problems, However, just the test is

Bandwidth or flow rate unit: Kbps Kbyte/sec Kilobytes per second Mbps Mbyte/sec Megabytes per second Kbit Kbits/sec Mbit Mbits/sec 1 , Analog Delay Transfer# TC Qdisc Add dev eth0 root netem delay 100msThis command sets the transmission of the eth0 NIC to a delay of 100 milliseconds to send.In a more realistic case, the delay value will not be so accurate, there will be a certain flu

, TCP communication, we know that TCP is reliable transmission-the sender of what I promise to send you intact, as for you to receive a look, oops, the bag stuck together how can I share clearly? Oops, this sent the data I parse out how is garbled? --It's not about TCP communications! This is your programmer to do the work of the message processing, the message transmission TCP to help you dry, and TCP is the name of the "Iron teeth sweet basil, honest and reliable little husband", has been ever

policy in Router 2, specifying host and port7 The ACL takes effect under the port of the Router 2 Xia Lian serverNetwork topology1 Configuring Router 1 single-arm routing, establishing sub-interfaces and configuring IP addresses, etc.2 Configuring the Switch's VLAN and port type3 Configuring the IP address of the PC4 Configuring the interface address for Router 25 Configure static routes to communicate properly between networks6 Configure the ACL policy on Router 2 to allow PC1 to access the se

Dma_alloc_cohrent . dma_addr_t *dma_map_single (struct device *dev, void *buffer, size_t size, enum dma_data_direction);function: A contiguous memory buffer is mapped to DMA memory for use. After mapping, the CPU can no longer manipulate this bufferReturn: The bus address of this buffer (physical address)Dev:null, too.Buffer: Virtual address of a contiguous memory eaSize: Amount of contiguous memoryDMA_DATA_DIRECTION:DMA the direction of the data streamNote: streaming DMA mapping , the memory

Analysis on network packet loss caused by full tracking of ip_conntrack connections When the access volume of our online web server is very large, packet loss occurs during network connection. You can view the log by running the dmesg command and find the following information: kernel:ip_conntrack:tablefull,droppingpac

CauseDo not know from when, colleagues began to fly in the autumn splash screen vibration, and later intensified, became a daily flash. Old Flash back also more trouble, as a procedural ape, there is no lazy way? (The colleague is responsible for the user experience and does not know programming). Then try the following ideas:UI AutomationUsing UISpy to view the autumn Chat window, sad to find that send the splash screen vibration button.Simulating mouse eventsReady to use Mouse_event to send mo

I. Lab Objectives Understand the principles and functions of NAT network address translation; Master the configuration of napt to enable LAN access to the Internet; Ii. Lab background The company's office network needs to access the Internet, and the company only applies for a leased line from the ISP. The leased line is assigned a public IP address, which allows all the company's hosts t

Our online Web server when the traffic is very large, there will be a network connection drops problem, through the DMESG command to view the log, the following information is found:Kernel:ip_conntrack:table full, dropping packet.kernel:printk:1 messages suppressed.kernel:ip_conntrack:table full, Dropping packet.kernel:printk:2 messages suppressed.kernel:ip_conntrack:table full, dropping packet.The key message is "ip_conntrack:table full, dropping

ports the current system launchesAnd[[email protected] ~]# Netstat-an//Print network connection Status TCP Three handshake four wave, need to focus on the content;Https://wenku.baidu.com/view/91793c1ec281e53a5802ff29.htmlShare the skill to see the number of all States (client and server in the number of communications, within 1000 is normal) [Email protected] ~]# Netstat-an | awk '/^tcp/{++sta[$NF]} END {for (key in STA) print key, "\ T

ObjectiveLearning Network knowledge of the students have heard or used the network device Simulator, network equipment simulator known to have Huawei's ENSP, Third HCl and Cisco PACKET TRACER, Cisco's simulator with a simple operation interface, Easy to install and use and a variety of easy to work can win a lot of

Packet Capture analysis is usually required when debugging network programs in Linux. Tcpdump in Linux is good. By default, Ubuntu has been installed. The following is a practical example. For example, I have a C ++ program listening to the local port 8889, and another newlisp program communicating with it through TCP. First, check several network interfaces. [Pl

Currently, we have completed a network packet capture tool, which is implemented in Python. The preferred library or interface for packet capture on Windows is Winpcap. Naturally, Winpcap programs close to the underlying system and hardware are generally written in C language, and the development interface provided by Winpcap is also C native. But fortunately, pe

A. WhatThe Charles tool makes it possible to intercept and analyze network packets by setting itself up as a network Access Proxy for the system so that all network access requests are done through it.It can achieve the followingSupport SSL Proxy: Intercepts the request to analyze SSL.Supports traffic control: simulates slow