use netstat to monitor receive queue Recv-Q

# i=0; while true; do i=$(($i+1)); echo $i ==============================; netstat -natlp | grep ^tcp | sort -nk1 | awk '{ if($2 != 0) {print}}' ; sleep 1;  done;
1 ==============================
2 ==============================
3 ==============================
4 ==============================
5 ==============================
tcp      100      0 10.0.3.167:22           198.21.8.23:53477       ESTABLISHED 99304/sshd: fordodone
6 ==============================
7 ==============================
8 ==============================
9 ==============================
tcp    43520      0 10.0.3.167:53877        10.0.9.55:3306          ESTABLISHED 119789/mysqldump
10 ==============================
11 ==============================
12 ==============================
13 ==============================
14 ==============================
15 ==============================
16 ==============================
tcp6       1      0 10.0.3.167:80           198.21.8.23:65114       CLOSE_WAIT  3880/apache2    
17 ==============================
18 ==============================
share:

wget monitor website download speed

# while true; do date | tr '\n' '-' | sed -e 's/-/ --- /'; wget http://testsite.com/fancy.pdf -O /dev/null 2>&1 | grep saved | awk -F"[()]" '{print $2}'; sleep 1s; done;
Thu Oct 30 15:18:26 PDT 2014 --- 1.25 MB/s
Thu Oct 30 15:18:28 PDT 2014 --- 1.20 MB/s
Thu Oct 30 15:18:29 PDT 2014 --- 958.95 KB/s
Thu Oct 30 15:18:31 PDT 2014 --- 1.36 MB/s
Thu Oct 30 15:18:32 PDT 2014 --- 873.98 KB/s
Thu Oct 30 15:18:33 PDT 2014 --- 1.38 MB/s
Thu Oct 30 15:18:35 PDT 2014 --- 261.90 KB/s
Thu Oct 30 15:18:37 PDT 2014 --- 1.38 MB/s
Thu Oct 30 15:18:38 PDT 2014 --- 360.14 KB/s
Thu Oct 30 15:18:40 PDT 2014 --- 1.37 MB/s
Thu Oct 30 15:18:42 PDT 2014 --- 427.06 KB/s
Thu Oct 30 15:18:44 PDT 2014 --- 1.37 MB/s
Thu Oct 30 15:18:45 PDT 2014 --- 397.54 KB/s
share:

Vyatta monitor and log NAT translation

Logging to record NAT translations. This might be helpful for finding users using bit torrent (along with tshark), or for watching what IPs are connecting to what external services, and when.

while true; do d=`date +%Y%m%d%H%M`; show nat translations detail | grep -v Pre-NAT | paste - - | sort -nk1 >nats.$d.log; sleep 5m; done;
# tail -1 nats.201408261250.log
a.a.a.a:21845    z.z.z.z:443     b.b.b.b:21845       z.z.z.z:443         tcp: snat: a.a.a.a ==> b.b.b.b  timeout: 42 use: 1 
share:

monitor NetApp SnapMirror transfer speed

You may want to monitor the speed of a current snapmirror to get an idea of how fast the transfer is going. The speed might change throughout the day due to load, or disk bottleneck, etc. I started with this one-liner:

i=0;j=0; while true; do j=$i; i=`ssh toaster01 "snapmirror status -l volname" | grep Progress | awk '{print $2}'| cut -d \( -f2`; if [ $j -eq 0 ]; then sleep 1m; continue; fi; echo -n "$i-$j = ";echo "scale=2;($i-$j)/(1024*1024)" | bc | tr '\n' ' '; echo "GB/min"; sleep 1m; done;

Which lead to this short script:

#!/bin/bash
# FILE: netapp_sm_monitor.sh
# AUTHOR: For Do Done <fordodone@fordodone.com>
# DATE: 2014/03/26
# NOTES: 
# 

if [ $# -lt 2 ]
then
  echo ""
  echo "usage: netapp_sm_monitor.sh <filer> <srcvol> [-v]"
  echo ""
  exit
fi

i=0;
j=0; 

while true; 
do 
  j=$i; 
  i=`ssh $1 "snapmirror status -l $2" | grep Progress | awk '{print $2}'| cut -d \( -f2`; 
  if [ $j -eq 0 ]; 
    then 
    sleep 1m; 
    continue; 
  fi; 
  if [ "$3" == "-v" ]
  then
    echo -n "$i-$j = ";
  fi
  echo "scale=2;($i-$j)/(1024*1024)" | bc | tr '\n' ' '; echo "GB/min"; 
  sleep 1m; 
done;
share:

monitor Apache memory usage

When looking at a webserver for memory usage, it’s important to consider the VSZ and RSS memory usage.

This little one liner gets the Total and Average VSZ and RSS usage as well as thread count, and prints those statistics every 5 seconds:

# while true; do ps auxfww | grep apache | grep -v -e cronolog -e grep | awk '{ vsum+=$5; rsum+=$6 } END { print "VSZ:", vsum, "(", vsum/NR, ") RSS:", rsum, "(", rsum/NR, ") Procs:", NR }'; sleep 5; done;
VSZ: 9896272 ( 341251 ) RSS: 1716216 ( 59179.9 ) Procs: 29
VSZ: 9547608 ( 340986 ) RSS: 1650100 ( 58932.1 ) Procs: 28
VSZ: 9546328 ( 340940 ) RSS: 1649044 ( 58894.4 ) Procs: 28
VSZ: 9861976 ( 340068 ) RSS: 1687968 ( 58205.8 ) Procs: 29
VSZ: 9868632 ( 340298 ) RSS: 1694496 ( 58430.9 ) Procs: 29
VSZ: 9853272 ( 339768 ) RSS: 1679112 ( 57900.4 ) Procs: 29
VSZ: 9853272 ( 339768 ) RSS: 1679264 ( 57905.7 ) Procs: 29
^C
#

So there are around 29 threads running right now on this server. The threads are using an average of 340MB per thread VSZ, and 59MB per thread RSS. The total of around 1.7GB of RSS looks good, on a machine with 8G physical memory.

share:

monitor host for slow ping times

When there is intermittent network latency to a host, it’s important to monitor a it for a pattern. Using ping can help narrow down what is causing the latency. VMWare load, bandwidth limitations, employee work patterns, backups, and many other sources could be the cause of the latency.

while true; do j=`ping <slowhost> -i1 -c1 2>&1 | grep icmp_req | awk '{print $7}' | cut -d = -f2 | cut -d . -f1`; if [ $j -gt 30 ]; then date | tr '\n' ' ';  echo $j; fi; sleep 1s; done;

This does a ping every second, and if it’s over a threshold (30ms in this case) it is considered unacceptable and logged with date.

share:

monitor host for connectivity

Sometimes, you want to be notified if a host goes up or down. Usually Nagios is perfect for this, but in this case I had an internet circuit, and all I cared about was knowing when the ISP deactivated it. Use ping in a loop, make 1 request every second, if ping doesn’t get a response, then send a text message (Verizon number) and stop the loop.

while true; do ping -nc 1 -W 1 5.6.7.8 | grep -q icmp; if [ "$?" == "1" ]; then echo "circuit is down" | mail <10-digit phone number no spaces>@vtext.com; break; fi; sleep 1s; done;

I also use the converse of this method when I want to know when a new circuit comes up.

share:

use command line to add pool and virtual server to f5 BigIP load balancer

Using the bigpipe cli command (or it’s alias “b“) to add pools and virtual servers, can save you hundreds of clicks. This is a very old version of a bigip.

# uname -r
BIG-IP 4.5.14

This creates a pool named myserverpool and adds a single member to it:

# b pool myserverpool {member 172.16.11.201:80}

To add many servers just use a while loop:

# i=202; while [ "$i" -lt "237" ]; do b pool myserverpool add \{ member 172.16.11.$i:80 \}; i=$(($i+1)); done;

Repeat for https:

# b pool myserverpool_ssl {member 172.16.11.201:443}
# i=202; while [ "$i" -lt "237" ]; do b pool myserverpool_ssl add \{ member 172.16.11.$i:443 \}; i=$(($i+1)); done;

Now add health checks:

# i=201; while [ "$i" -lt "237" ]; do b node 172.16.11.$i:80 monitor use http; i=$(($i+1)); done;
# i=201; while [ "$i" -lt "237" ]; do b node 172.16.11.$i:443 monitor use https; i=$(($i+1)); done;

And finally create the virtual servers, pointing traffic to the corresponding pools:

# b virtual 5.6.7.8:80 use pool myserverpool
# b virtual 5.6.7.8:443 use pool myserverpool_ssl
share: