Commands by jp (2)

  • Network traffic on NICs in mbps without sar, iperf, etc...

    Need output in mbps (bits) # ./bytes-second.sh eth0 eth0 interface maximum Speed: 1000Mb/s RX:12883212 TX:17402002 B/s | RX:98 TX:132 Mb/s RX:12371647 TX:17830111 B/s | RX:94 TX:136 Mb/s RX:12502750 TX:17860915 B/s | RX:95 TX:136 Mb/s Show Sample Output


    1
    RX1=`cat /sys/class/net/${INTERFACE}/statistics/rx_bytes` (see script below)
    jp · 2012-01-23 18:22:44 10
  • ssh batch jobs: query hundreds of hosts with an ssh command

    Need to query hundreds of hosts with an ssh command ? Of course you'll have setup keys on all your remote HOSTs. But in the case a key is not present this command will skip that node, proceeding on to the next. -t: Force pseudo-tty allocation. This can be used to execute arbitrary screen-based programs on a remote machine. Also prevents unwanted stty messages being sent to console -q: Quiet mode. -o "BatchMode yes" If set to yes, passphrase/password querying will be disabled. This option is useful in scripts and other batch jobs where no user is present Show Sample Output


    1
    ssh -tq -o "BatchMode yes" $HOST <some_command> >> to_a_file
    jp · 2011-03-02 20:33:59 3

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