MTUIt is the abbreviation of maximum transmission unit, which is the largest transmission unit.Maximum packet transmitted over the networkIn bytes.
Ethernet imposes a limit on the length of data frames. The maximum value is 1500. This feature is called MTU. Most of different types of networks have an upper limit. If an IP packet is to be transmitted on the IP layer and the data length is greater than the MTU value on the link layer, the packet must be
configThis command shows non-default invocations only.Use 'show config all' to show both default and non-default deployments..............................Begin!# ***** NON-DEFAULT CONFIGURATION *****!!# Time: Thu May 2 2002, 01:26:26!# Version 5.5 (14)!!# SystemSet system name comment st6500!#!# VtpSet vtp mode transparentSet vlan 1 name default type ethernet mtu 1500 said 100001 state activeSet vlan 2 name VLAN0002 type ethernet mtu
larger than 1500 bytes. The transmission layer of the sender node divides the data into smaller data slices, and arranges a serial number for each data segment so that the data can reach the transmission layer of the receiver node, the process can be reorganized in the correct order, which is called sorting. It uses the maximum transmission unit value that sends a group to the network interface on the link. All parts of the original group are marked,
1. Select * from EMP;
2. Select Empno, ename, job from EMP;
3. Select empno number, ename name, job work from EMP;
4. Select Job from EMP;
5. Select distinct job from EMP;
6. Select distinct empno, job from EMP;Note: Because the employee number is not duplicated, it is not possible to eliminate duplicate columns by proving that all the columns are not duplicated at this time.
7. Query the employee's number, name, work, but display the format: 7369 employee, name is: Smith, work is: clearSe
Oracle query syntax
1. Select * from EMP;
2. Select empno, ename, job from EMP;
3. Select empno number, ename name, job from EMP;
4. Select job from EMP;
5. Select distinct job from EMP;
6. Select distinct empno, job from EMP;Note: Because employee numbers are not repeated, it is proved that all columns are not repeated at this time, so repeated Columns cannot be eliminated.
7. query the employee ID, name, and work, but the displayed format is: 7369 employee, name: Smith, and work: ClearSelect
This article summarizes the good, from: http://hi.baidu.com/to_wait/blog/item/3e855931a5a51717eac4af22.html
The TCP/IP protocol involves four layers: link layer, network layer, transmission layer, and application layer.The Ethernet data frame is at the link layer.IP packageAt the network layerTCP or UDP PacketsAt the transport layerData in TCP or UDP(Data) at the application layerTheirLink isData frame {IP packet {TCP or UDP packet {data }}}-------------------------------------------------------
1.
Select* From EMP;
2. Select empno, ename, job from EMP;
3. Select empno number, ename name, jobWorkFrom EMP;
4. Select job from EMP;
5. Select distinct job from EMP;
6. Select distinct empno, job from EMP;Note: Because employee numbers are not repeated, it is proved that all columns are not repeated at this time, so repeated Columns cannot be eliminated.
7.QueryEmployee ID, name, work, but displayed in the format of: 7369 employee, name: Smith, job: ClearSelect ':' | empno | 'employee, name:
1. select * from emp;
2. select empno, ename, job from emp;
3. select empno number, ename name, job from emp;
4. select job from emp;
5. select distinct job from emp;
6. select distinct empno, job from emp;Note: Because employee numbers are not repeated, it is proved that all columns are not repeated at this time, so repeated Columns cannot be eliminated.
7. query the employee ID, name, and work, but the displayed format is: 7369 employee, name: smith, and work: clearSelect ':' | empno | 'employ
I. CAT4006 engine module WS-X4013 configuration listThese include: Basic settings, VLAN configuration, Channel configuration, and port Image Port 1/2 to connect to gigabit IDS)
Cisco Systems, Inc. Console
Enter password:CAT4006> enable
Enter password:CAT4006> (enable).....................................................................................
Begin!# ***** NON-DEFAULT CONFIGURATION *****!!# Time: Mon Apr 11 2005, 22:02:13!# Version 6.1 (1)!!# System web interface version (s)Set password
I recently learned about UDP programming and got a big head. I have found a lot of materials and consulted many colleagues. I think the following information is well written, so I collected it for reference.1. During UDP programming, the most common question is how many bytes are sent at a time?Of course, there is no unique answer. The answer to this question varies with the requirements of different systems.For example, if you want to analyze the situation of sending chat messages like ICQ, you
Connection query category
1. Self-join query, connecting to the same table2. internal join query, [divided into: Natural join (that is, equivalent join removes duplicate rows, or select the column to be represented after select, instead of using "*" to list all columns), equijoin (that is, use "=" for logical judgment after where), non-equijoin]
[During inner join, the returned result set is only the rows that meet the query and connection conditions .]3. External Connection query, which can
. Compare the transmission time of A 3.4G ISO from server A scp to server B.Data goes through the Business Link and bonding technology is not used.############# No Binding ##############[Root @ rac-node01 tmp] # time scp rhel-5.1-server-x86_64-dvd.iso 10.168.0.202:/tmpRoot@10.168.0.202's password:Rhel-5.1-server-x86_64-dvd.iso 100% 3353 MB 44.1 MB/s 0
Real 1m20. 105 sUser 0m34. 752 sSys 0m11. 002 s############# FastThe data follows the heartbeat link and uses the bonding technology. The mode is
/nvidia. ko overwrite/lib/modules/2.6.18-8. el5xen/kernel/drivers/video/nvidia. ko)
Mkdir/lib/modules/2.6.18-8. el5xen/kernel/drivers/video/nvidia
Cp nvidia. ko/lib/modules/2.6.18-8. el5xen/kernel/drivers/video/nvidia
6. depmod-
Reboot
7. Main Menu-> system-> Management-> display
Hardware-> video card type (configuration)-> nvidia-Vendor-supplied driver for nvidia cards-> OK
[Note] And then log on again. The system has used the nvidia official driver, and the projection output and high resol
and hard disk capacity can be upgraded. Replacing the latest hard disk with a 5400-to-10% ~ An increase of about 15% is satisfactory in terms of noise and energy consumption.
For a laptop, there will never be too much memory. In order to make up for the inherent shortage of hard disk performance, we need more memory capacity to support it. I have tested on my laptop. When the standard memory is 20% MB, the disk performance ratio decreases by nearly 244 (the pcmark2002 HDD score is 296 and res
Kernel configuration considerations
If you want to compile the kernel yourself (the kernel source code can be downloaded to the ftp://ftp.kernel.org/pub/kernel/, domestic download can be to the ftp://ftp.cn.kernel.org/pub/kernel/ so that download faster), before the compilation usually need to use make menuconfig or make xconfig to configure the kernel. My system does not have xconfig, so I can only use menuconfig. Note the following when compiling the 2.6.23.x Kernel on my Compaq
I believe that the 99 SQL statements are handled, and the basic Oracle test is just like playing (the most comprehensive and most typical entry-level Oracle query statements in history)
1. select * from emp;2. select empno, ename, job from emp;3. select empno number, ename name, job from emp;4. select job from emp;5. select distinct job from emp;6. select distinct empno, job from emp;Note: Because employee numbers are not repeated, it is proved that all columns are not repeated at this time, so
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.