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How to install netstatnetstat is a useful tool for checking your network configuration and activity. The netstat CommandDisplaying the Routing TableWhen you invoke netstat with the –r flag, it displays the kernel routing table in the way we’ve been doing with route. On vstout, it produces: # netstat -nrKernel IP routing tableDestination Gateway Genmask Flags MSS Window irtt Iface127.0.0.1. 255.255.255.255 UH 0 0 0 lo172.16.1.0. 255.255.255.0 U 0 0 0 eth0172.16.2.0 172.16.1.1 255.255.255.0 UG 0 0 0 eth0The –n option makes netstat print addresses as dotted quad IP numbers rather than the symbolic host and network names.
How To Install Tcpstat Windows
This option is especially useful when you want to avoid address lookups over the network (e.g., to a DNS or NIS server).The second column of netstat‘s output shows the gateway to which the routing entry points. If no gateway is used, an asterisk is printed instead. The third column shows the “generality” of the route, i.e., the network mask for this route. When given an IP address to find a suitable route for, the kernel steps through each of the routing table entries, taking the bitwise AND of the address and the genmask before comparing it to the target of the route.The fourth column displays the following flags that describe the route: GThe route uses a gateway.UThe interface to be used is up.HOnly a single host can be reached through the route. For example, this is the case for the loopback entry 127.0.0.1.DThis route is dynamically created. It is set if the table entry has been generated by a routing daemon like gated or by an ICMP redirect messageMThis route is set if the table entry was modified by an ICMP redirect message.!The route is a reject route and datagrams will be dropped.The next three columns show the MSS, Window and irtt that will be applied to TCP connections established via this route. The MSS is the Maximum Segment Size and is the size of the largest datagram the kernel will construct for transmission via this route.
The Window is the maximum amount of data the system will accept in a single burst from a remote host. The acronym irtt stands for “initial round trip time.” The TCP protocol ensures that data is reliably delivered between hosts by retransmitting a datagram if it has been lost. The TCP protocol keeps a running count of how long it takes for a datagram to be delivered to the remote end, and an acknowledgement to be received so that it knows how long to wait before assuming a datagram needs to retransmitted; this process is called the round-trip time. The initial round-trip time is the value that the TCP protocol will use when a connection is first established. For most network types, the default value is okay, but for some slow networks, notably certain types of amateur packet radio networks, the time is too short and causes unnecessary retransmission. The irtt value can be set using the route command.
Values of zero in these fields mean that the default is being used.Finally, the last field displays the network interface that this route will use.Displaying Interface StatisticsWhen invoked with the –i flag, netstat displays statistics for the network interfaces currently configured. If the –a option is also given, it prints all interfaces present in the kernel, not only those that have been configured currently. On vstout, the output from netstat will look like this: # netstat -iKernel Interface tableIface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flagslo 0 0 3185 0 0 0 3185 0 0 0 BLRUeth0 1500 0 972633 17 20 120 628711 217 0 0 BRUThe MTU and Met fields show the current MTU and metric values for that interface.
How To Install Tcpstat Screen
The RX and TX columns show how many packets have been received or transmitted error-free (RX-OK/TX-OK) or damaged (RX-ERR/TX-ERR); how many were dropped (RX-DRP/TX-DRP); and how many were lost because of an overrun (RX-OVR/TX-OVR).The last column shows the flags that have been set for this interface. These characters are one-character versions of the long flag names that are printed when you display the interface configuration with ifconfig: BA broadcast address has been set.LThis interface is a loopback device.MAll packets are received (promiscuous mode).OARP is turned off for this interface.PThis is a point-to-point connection.RInterface is running.UInterface is up.Displaying Connectionsnetstat supports a set of options to display active or passive sockets. The options –t, –u, –w, and –x show active TCP, UDP, RAW, or Unix socket connections.
If you provide the –a flag in addition, sockets that are waiting for a connection (i.e., listening) are displayed as well.