Common prompts and meanings on the LINUX Server front-end

Common prompts and meanings on the front-end of a LINUX Server-Linux Enterprise Application-Linux server application information. For more information, see the following. General class prompts
Eth1: Too much work at interrupt, IntrStatus = 0x0001
The meaning of this prompt is. A network card has too many interrupted requests. if it appears only once, it can be ignored. however, if this prompt appears frequently or appears in a centralized manner, there are many possibilities involved that need to be processed. there are many possibilities, such as NIC performance, server performance, and network attacks .. and so on.

General class prompts
IPVS: incoming ICMP: failed checksum from 61.172.0.X!
The server has received an ICMP packet with a checksum and an error. This type of data packet may be generated illegally. However, the server has received a lot of such data, which is generally ignored.
Generally, the proxy server forwards thousands of data packets every second during work. receiving several error data packets does not affect normal operation.
This is the most frequently asked type of prompt.

General class prompts
NET: N messages suppressed.
The server ignores N Packets. Similar to the previous prompt, the packets received by the server are considered useless junk data. This type of data is mostly generated by attack programs.
This prompt can be ignored if N is relatively small. However, if such a prompt appears frequently or for a long time, it is likely that the server is under a bandwidth attack like junk data.

General class prompts
UDP: bad checksum. From 221.200.X.X: 50279 to 218.62.X.X: 1155 ulen 24
UDP: short packet: 218.2.X.X: 3072 3640/217 to 222.16x.x: 57596
218.26.131.X sent an invalid ICMP type 3, code 13 error to a broadcast: 0.1.0.4 on eth0
The server receives an incorrect packet, Which is UDP checksum and error, too short UDP packet, and an incorrect ICMP data packet. This type of information is generally invalid.
But the general problems are not big and can be ignored directly.

General class prompts
Kernel: conntrack_ftp: partial 227 2205426703 + 13
FTP_NAT: partial packet 2635716056/20 in 2635716048/2635716075
An error occurs when the server maintains an FTP connection. Such a prompt can be ignored directly.

Serious network communication problems!
Netdev watchdog: eth1: transmit timed out
Eth1: link down
Eth1: link up, 10 Mbps, half-duplex, lpa 0x0000
Eth2: link up, 100 Mbps, full-duplex, lpa 0x41E1
Setting full-duplex based on MII #24 link partner capability of 45e1
These prompts appear only when serious problems occur in network communication. the fault is basically related to network disconnection. these prompts indicate that data transmission times out for a certain network adapter, the network adapter is down, the network adapter is up, and the connection rate is 10/100 Mbps.
The last three lines of prompts written here are similar. When such prompts appear, you must pay attention to the network connection status for processing !!!

Serious network communication problems!
NIC Link is Up 100 Mbps Full Duplex
Situation and kernel: eth1: link up ,... same. the connection rate that a network card can adapt. it is generally considered that the network adapter is down, but the adaptive speed of the network adapter is also a communication problem.
This type of information can be ignored if the network cable is disconnected normally.

Serious network communication problems!
Eth0: Transmit timed out, status 0000, PHY status 786d, resetting...
Eth0: Reset not complete yet. Trying harder.
The first prompt indicates that the NIC fails to send data. Reset the NIC. The second prompt indicates that the NIC is not successfully reset... These prompts are all serious communication problems.

Alarm program prompt
0001 ## WMPCheckV001 ## 2005-04-13_10: 10: 01 Found. (ARP Spoofing sniffer )! IP: 183 MAC: 5
0002 ## WMPCheckV001 ## 2005-04-07_01: 53: 32 Found. (MAC_incomplete )! IP: 173 mac_incomplete: 186
0003 ## WMPCheckV001 ## 2005-04-17_16: 25: 11 Found. (HIGH_synsent )! Totl: 4271 SynSent: 3490
0004 ## WMPCheckV001 ## 20 ......
This is a prompt caused by the alarm program. For details, use the client of the alarm program to receive the message in real time. For details, see "alarm module and log ".

General class prompts
Eth1: Promiscuous mode enabled.
Device eth1 entered promiscuous mode
Device eth1 left promiscuous mode
These rows indicate. A network card enters (left) hybrid mode. generally, the hybrid mode is used only when packet capture is required for communication. when maintenance or fault analysis is used (such as the countflow command in consoletools ). this type of prompt can be ignored.
This prompt should be noted if no maintenance is performed on both the frontend and the remote end, but this is unlikely.

Basic irrelevant
Keyboard: unknown scancode e0 5e
Undefined key values are received on the keyboard. If this occurs frequently, it may be caused by a keyboard problem. For linux, such a prompt is sometimes prompted for special keys or key combinations.
Check whether the server's keyboard is pressed. Otherwise, ignore it.

Basic irrelevant
Uses obsolete (PF_INET, SOCK_PACKET)
The system kernel calls some functional modules, which may occur during the first call. This is generally related to the use of debugging tools.

Network Communication fault
Neighbour table overflow.
This prompt appears. Generally, some computers in the LAN are infected with viruses. In severe cases, communication may be affected. Computers with abnormal Intranet Communication must be processed.

Network Communication fault
Eth1: Transmit error, Tx status register 82.
Probably a duplex mismatch. See Documentation/networking/vortex.txt
Flags; bus-master 1, dirty 9994190 (14) current 9994190 (14)
Transmit list 00000000 vs. f7171580.
0: @ f7171200 length 800001e6 status 000101e6
1: @ f7171240 length 8000008c status 0001008c
....
This prompt is available for 3com. I feel that it will not be very serious if it appears. currently, the solution to the problem is to replace the NIC on the server. I really feel that 3com Nic has some problems...

Serious server system faults
CPU0: Temperature above threshold
CPU0: Running in modulated clock mode
The operating temperature of the server CPU is too high. hardware faults must be ruled out.