many concurrent smtp connections

How to view Web Service concurrent Solicitation Connections 1, View Web service (Nginx Apache) concurrent pleading number and its TCP connectivity status: Netstat-n | awk \ '/^tcp/{++s[$NF]} END {for (a in S) print a, s[a]}\ ' netstat-n|grep ^tcp|awk \ ' {print $NF}\ ' |sort-nr|uniq-c or: Net Stat-n | awk \ '/^tcp/{++state[$NF]} END {for (key on state) print key,

// when keep-alive is enabled, this value is equal to active-(reading + writing), meaning Nginx has processed the resident connection Waiting for the next request command. 2. View through commands View commands 1 $ Netstat-n | awk '/^ tcp/{++ S [$ NF]} END {for (a in S) print a, S [a]}' Result 1 2 3 4 5 6 7 TIME_WAIT 17 ESTABLISHED 3254 LAST_ACK 236 FIN_WAIT_1 648 FIN_WAIT_2 581 CLOSING 7 CLOSE_WAIT 4916 Result description

By viewing the Nginx concurrent connections, we can clear the load of the website. There are two ways to view Nginx concurrency (the reason is that I only know two ways), one is through the web interface, the other is through the command, web View is more accurate than command view. The following describes the two viewing Methods: No1, through the browser to view through the web interface to view Nginx need

By viewing the Nginx concurrent connections, we can clear the load of the website. There are two ways to view Nginx concurrency (the reason is that I only know two ways), one is through the web interface, the other is through the command, web view is more accurate than Command View. The following describes the two viewing methods No1. when viewing through a browser through the web interface, Nginx needs to

1. View the number of concurrent requests for Webserver (Nginx Apache) and their TCP connection status:Netstat-n | awk '/^tcp/{++s[$NF]} END {for (a in S) print A, s[a]} 'Netstat-n|grep ^tcp|awk ' {print $NF} ' |sort-nr|uniq-cOr:Netstat-n | awk '/^tcp/{++state[$NF]} END {for (key in) print key, "T", State[key]} 'The returned results are generally as follows:Last_ack 5 (number of requests waiting to be processed)SYN_RECV 30Established 1597 (normal tran

;%tmpdir%\listeningType%tmpdir%\%1 | FIND/C "Timewait" >%tmpdir%\time_waitType%tmpdir%\%1 | FIND/C "Timeclose" >%tmpdir%\time_closeType%tmpdir%\%1 | FIND/C "Synsent" >%tmpdir%\synsentType%tmpdir%\%1 | FIND/C "FINWAIT1" >%tmpdir%\fin1Type%tmpdir%\%1 | FIND/C "FINWAIT2" >%tmpdir%\fin2Type%tmpdir%\%1 | FIND/C "Synrecv" >%tmpdir%\synrecvset/p established= set/p listening= set/p time_wait= set/p time_close= set/p synsent= set/p fin1= set/p fin2= set/p synrecv= ECHO established:%established% listen:%l

During web engineering Debugging Over the past few days, too many connected users are always prompted. So I decided to find a method to crack IIS connection restrictions, but it ended in failure. Through a one-morning experiment, we found that, in the methods we can find, no matter whether we modify the registry, use the modification tool provided by MS, or use something similar to a patch, We can't lift the restrictions on concurrent IIS

To support over 500k users, *need*-A -Bits hardware/Kernel (AMD64, opterons)-At least 8GB of RAM-A recent Linux kernel (2.6. x) About tuning, I prefer to not fully disclose them because servers is targets of many attacks, so it's better not to help hackers.The most touchy thing isThe IP Route cache:you has to tune it orElseThe machine drops many connections (hint:rhash_entries=...inchThe boot appendstring) Hints:echo1>/proc/sys/net/ipv4/route/Gc_inter

Police Notice:650) this.width=650; "Src=" Http://s1.51cto.com/wyfs02/M00/8C/8D/wKiom1hvcnvwiLJJAAB89iKdqgE168.png-wh_500x0-wm_3 -wmp_4-s_4237838755.png "title=" 2.png "alt=" Wkiom1hvcnvwiljjaab89ikdqge168.png-wh_50 "/>This is because the Exchange receive connector has concurrency limitations.You can query with the following command:650) this.width=650; "Src=" Http://s4.51cto.com/wyfs02/M01/8C/8D/wKiom1hvdADTor_0AAALTB_W_HQ691.png-wh_500x0-wm_3 -wmp_4-s_1507404036.png "title=" 3.png "alt=" Wkiom1

Netstat-nt|awk ' {++s[$NF]}end{for (A in S) print A,s[a]} ' time_wait 49State 1ESTABLISHED 777servers) 1LISTEN: The server is waiting to enter the callSYN_RECV: A connection request has arrived, waiting for confirmationsyn_sent: Application has started, open a connectionestablished: Normal data transfer statusfin_wait1: Application says it's doneFin_wait2: The other side has agreed to releaseitmed_wait: Waiting for all packets to dieCLOSING: Both sides try to close simultaneouslytime_wait: The o

Netstat command and awk to view the number of concurrent connections to the Web server and the TCP connection status. The code is as follows Copy Code Netstat-n | awk '/^tcp/{++s[$NF]} end {for (a in S) print A, s[a]} 'Or:Netstat-n | awk '/^tcp/{++state[$NF]} end {for (key) print key, "T", State[key]} ' Fin_wait2 38CLOSING 3SYN_RECV 1Close_wait 1Time_wait 261Establishe

pool, executes the SQL, obtains the result, and then returns the database connection to the database connection pool.If a session, perform 10 independent operations. If you do not use a database connection pool, you need to create a database connection 10 times and close 10 times. Using a database connection pool, directly using the database connection pool is already open and ready to use.4. SolutionA, in the code, the closed database connection shut down and release resourcesb, expand the sha

connections by default. For a communication handler that wants to support a higher number of TCP concurrent connections, you must modify the soft limit (soft limit) and the hard limit (hardlimit) of the number of files that Linux has open simultaneously for the current user's process. The soft limit refers to the Linux in the current system can withstand the ext

TIME_WAIT state hold time is not long enough (for example, less than 2MSL), the first connection terminates normally. A second connection with the same related five-tuple appears, and the first concatenated duplicate message arrives, interfering with the second connection. The TCP implementation must prevent a duplicate message of a connection from appearing after the connection is terminated, so that the time_wait state is kept long enough (2MSL), and the TCP message in the corresponding direc

, this place is also I began not to pay attention to the place, determined after pressing ctrl+x key to exit back to the command line The last step is to restart MySQL. The code is as follows Copy Code [root@localhost ~]# Service mysqld restart//restart MySQL command below is my own CentOS under the test pass View the maximum number of connections to MySQL settings under the current system The code

1. View the number of concurrent requests for the Web server (Nginx Apache) and its TCP connection status:Netstat-n | awk '/^tcp/{++s[$NF]} END {for (a in S) print A, s[a]} 'Netstat-n|grep ^tcp|awk ' {print $NF} ' |sort-nr|uniq-cOr:Netstat-n | awk '/^tcp/{++state[$NF]} END {for (key in) print key, "T", State[key]} 'The returned results are generally as follows:Last_ack 5 (number of requests waiting to be processed)SYN_RECV 30Established 1597 (normal d

1. View the number of concurrent requests for the Web server (Nginx Apache) and its TCP connection status:Netstat-n | awk '/^tcp/{++s[$NF]} END {for (a in S) print A, s[a]} 'Netstat-n|grep ^tcp|awk ' {print $NF} ' |sort-nr|uniq-cOr:Netstat-n | awk '/^tcp/{++state[$NF]} END {for (key in) print key, "T", State[key]} 'The returned results are generally as follows:Last_ack 5 (number of requests waiting to be processed)SYN_RECV 30Established 1597 (normal d

Original link: Http://stackoverflow.com/questions/17593699/tcp-ip-solving-the-c10k-with-the-thread-per-client-approach It is possible for a thread to support 10,000 concurrent connections with one connection. However, the following issues need to be noted: (1) A thread A customer connection, when the customer exit needs, delete the thread, when the new thread arrives, need to create a new thread,

() { return Conn; } } Before using the SQL Server database connection did not have any problems, and later find the data found this is a MySQL connection bug. The official website is described as follows: https://bugs.mysql.com/bug.php?id=7248 MySql.Data.MySqlClient.MySqlException:There is already a open DataReader associated with this Connection which must be C losed first. That is, only one connection is allowed to be opened to read data at the same time. The