Q. How do I display summary statistics for each protocol on Linux ?
A. Using netstat command to display summary statistics for each protocol.
netstat command
netstat (network statistics) is a command-line tool that displays network connections (both incoming and outgoing), routing tables, and a number of network interface statistics. It is available on Unix, Unix-like, and Windows NT-based operating systems.
Display summary statistics using netstat
Simply use netstat -s
# netstat -s
Ouput
Ip:
927340778 total packets received
7 with invalid headers
1959 with invalid addresses
0 forwarded
0 incoming packets discarded
922379597 incoming packets delivered
1280879573 requests sent out
27 outgoing packets dropped
4 fragments dropped after timeout
757 reassemblies required
354 packets reassembled ok
4 packet reassembles failed
20 fragments failed
Icmp:
36541 ICMP messages received
124 input ICMP message failed.
ICMP input histogram:
destination unreachable: 26890
timeout in transit: 348
source quenches: 11
echo requests: 9274
echo replies: 1
18720 ICMP messages sent
0 ICMP messages failed
ICMP output histogram:
destination unreachable: 9446
echo replies: 9274
IcmpMsg:
InType0: 1
InType3: 26890
InType4: 11
InType8: 9274
InType11: 348
OutType0: 9274
OutType3: 9446
Tcp:
5916623 active connections openings
36244722 passive connection openings
102606 failed connection attempts
3493764 connection resets received
53 connections established
918246879 segments received
1254505238 segments send out
22244556 segments retransmited
0 bad segments received.
5748855 resets sent
Udp:
4086750 packets received
9427 packets to unknown port received.
0 packet receive errors
4125646 packets sent
...
To display the statistics for only the TCP or UDP protocols, type one of the following commands
# netstat -st # netstat -su
Ouput
IcmpMsg:
InType0: 1
InType3: 26890
InType4: 11
InType8: 9274
InType11: 348
OutType0: 9274
OutType3: 9446
Tcp:
5917335 active connections openings
36247817 passive connection openings
102606 failed connection attempts
3493814 connection resets received
29 connections established
918349626 segments received
1254667978 segments send out
22246760 segments retransmited
0 bad segments received.
5749332 resets sent
...
To display the quick interfaces statistics, type the following command
# netstat -i
Ouput
Kernel Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eth0 1500 0 767575580 0 0 0 1120000223 0 0 0 BMRU lo 16436 0 161102011 0 0 0 161102011 0 0 0 LRU
To display the extended interfaces statistics, type the following command
# netstat -ie
Ouput
Kernel Interface table
eth0 Link encap:Ethernet HWaddr 00:25:90:0B:A3:E4
inet addr:221.132.34.8 Bcast:221.132.34.95 Mask:255.255.255.224
inet6 addr: fe80::225:90ff:fe0b:a3e4/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:767588970 errors:0 dropped:0 overruns:0 frame:0
TX packets:1120021944 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4030025515 (3.7 GiB) TX bytes:2208549264 (2.0 GiB)
Interrupt:169 Memory:fb5e0000-fb600000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:161106440 errors:0 dropped:0 overruns:0 frame:0
TX packets:161106440 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3387569934 (3.1 GiB) TX bytes:3387569934 (3.1 GiB)