how to troubleshoot packet loss in network

in front of the Libpcap capture packet, especially in the gigabit network conditions, a large number of drops, online search for a long time, probably all Pf_packet +mmap,napi,pf_ring and other methods, I pf_ring+libpcap experiment, The detection of gigabit network conditions, capturing the performance of the packet is

Routing RingNetwork Packet Loss This is an actual case of analyzing the causes of a large number of packet loss on the network. The user's network packet

The network port uses the 1000M rate time to appear the network communication loses the packet +idc the computer room managed server communication is not smooth. Network failure: Switch port 1000M, network card is 1000M, NIC configuration is normal. You lose the

Analyze the network traffic of this host After determining that a large volume of sent traffic on the host is the main cause of network congestion, we need to further analyze the traffic on the host, that is, what the host is doing on the network, it can be referred to as analyzing his network behavior. First, we analy

Let's start by recognizing what a packet loss is, and what kind of phenomenon is being lost to the network: Data is transmitted on the Internet on a packet-by-unit basis, with a packet of NK, no more, no less. That is to say, no matter how good the

1 Introduction to Analog delay transferNetem and Tc:netem are a network emulation function module provided by Linux 2.6 and above kernel versions. The function module can be used to simulate complex Internet transmission performance in a well-performing LAN, such as low bandwidth, transmission delay, packet loss and so on. Many distributions of Linux with Linux 2

1 Introduction to Analog delay transmission Netem and Tc:netem are a network emulation module provided by the Linux kernel version 2.6 and above. This function module can be used to simulate complex Internet transmission performance in a well performing LAN, such as low bandwidth, transmission delay, packet loss, and so on. Many distributions Linux that use the L

Let's start by recognizing what a packet loss is, and what kind of phenomenon is being lost to the network: Data is transmitted on the Internet on a packet-by-unit basis, with a packet of NK, no more, no less. That is to say, no matter how good the

, we set the maximum limit of 4,096, is the driver inside each receive a batch of packets, it will ixgbe_alloc_rx_buffers assign a batch of new SKB and pagePCI_DMA mapping to the hardware to collect packetsHere the first Tasklet dispatch to CPU1, cpu2 the problem can be explained, the VM packet triggered the network card cpu1, cpu2 on the interruption, until soft interrupt, KFREE_SKB, Trigger Idx_release, t

Previously, we talked about libpcap packet capture, especially in the case of a gigabit network, which results in a large number of packet loss and a long time of searching on the Internet. This is probably a method like PF_PACKET + MMAP, NAPI, and PF_RING, I tested PF_RING + libpcap and found that the

whether there is any traffic exception. Network Traffic Analysis Process 1. Overall Network Traffic Monitoring We first use the History Samples historical sampling function of Sniffer Pro to monitor the network utilization on the image link. The following results are obtained: Link to utilization The link actually transmits numbers per second. From the above

to the client to perform network debugging two months ago. Its Internet cafe covers an area of more than seven hundred square meters and has 120 machines. It is equipped with a dedicated data center and is equipped with switches and servers. I took my laptop to its dedicated data center. The first step was to test the telecom terminal, connect the portable device to the photoelectric converter, configure the portable device with an IP address, ping t

Resolve network packet loss problems in linuxRecently, I encountered problems in my business. I found that the value of overruns is constantly increasing. I learned some related knowledge.It is found that the number is constantly increasing. G, I found that the meanings of these errors, dropped, and overruns are not the same.Eth2 Link encap: Ethernet HWaddr 00: 8

Solution 1: Disable all switches in the LAN five minutes later. Power on again to check if the network is back to normal! (Cause: it may be that the switch has used up its memory for a long time without restarting, resulting in slow data exchange speed or congestion caused by network storms) (another possible cause is that one or more interface modules of a vswitch are damaged, or an internal

FEC (Forward error Correction) forward error correction UDP\RTP used to improve wireless and other network packet loss problems The algorithm is not introduced at this stage. Idea: FEC ENCODE adds redundant packets, and when the wireless network drops packets, the receiver uses redundant packets to decode the lost pa

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

Clone Zabbix's own template ICMP ping templates 650) this.width=650; "Src=" Http://s5.51cto.com/wyfs02/M01/86/F3/wKioL1fPrcLi2YxjAAByYarcCOM203.jpg-wh_500x0-wm_3 -wmp_4-s_2806794333.jpg "title=" ping 202.96.209.5.jpg "alt=" Wkiol1fprcli2yxjaabyyarccom203.jpg-wh_50 "/>Here I make a network delay template to 202.96.209.5 Shanghai DNS650) this.width=650; "Src=" Http://s3.51cto.com/wyfs02/M02/86/F3/wKioL1fPrnnS2DkyAACNTuKAcik725.jpg-wh_500x0-wm_3 -wm

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 d

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

-- bandwidth 200000[Root @ localhost nistnet-3.0a] # The above is the command script of the basic server. Generally, you can use cnistnet-u to check whether it is started. If it is not started, a script without a directory will be reported, after the startup, use cnistnet-R to view the status. You can view the latency, jitter, and packet loss related to the control. It is found that the cnistnet software i