Linux connection count status Statistics

Statistics on the number of connections in linux connection status: netstat has poor performance when the number of connections exceeds 4 W. Let's take a look at the ss command: ss-t-a # count all TCP connections ss-u-a # count all UDP connections ss also has the filter function, the following lists the common functions: ssstate... statistics on the number of connections in linux connection status: netstat has poor performance when the number of connections exceeds 4 W. First look at the ss command: ss-t-a # count all TCP connections ss-u-a # count all UDP connections
Ss also has the filtering function. The following lists common functions: ss state ESTABLISHED # List all connections in the ESTABLISHED state ss-t-a-o excl ESTABLISHED # exclude all connections in the ESTABLISHED state
Ss state ESTABLISHED sport eq: 80 # List all connections in the status of ESTABLISHED on port 80. ss state ESTABLISHED sport eq: 80 and not dst 127.0.0.1 # List all connection ss commands in the status of ESTABLISHED and the destination address is not 127.0.0.1 on port 80 from the iproute package. Ss-s lists some basic statistics: # ss-sTotal: 43160 (kernel 43254) TCP: 43770 (estab 43069, closed 32, orphaned 646, synrecv 0, timewait 24/0), ports 285 Transport Total IP IPv6 * 43254-RAW 0 0 UDP 13 10 3 TCP 43738 43535 203 INET 43751 43545 206 FRAG 0 0 0TCP :? 43770? (Estab 43069 ,? Closed 32 ,? Orphaned 646 ,? Synrecv 0 ,? Timewait 24/0 ),? What does this line of ports 285 mean? you can only find it in the source code :... printf ("TCP: % d (estab % d, closed % d, orphaned % d, synrecv % d, timewait % d/% d), ports % d \ n ", s. tcp_total + slabstat. tcp_syns + s. tcp_tws, sn. tcp_estab, s. tcp_total-(s. tcp4_hashed + s. tcp6_hashed-s.tcp_tws), s. tcp_orphans, slabstat. tcp_syns, s. tcp_tws, slabstat. tcp_tws, slabstat. tcp_ports );