I wrote a simple script to get IPv4 addresses, as follows:
#!/bin/bash
ip -4 addr | grep inet | awk -F '[ \t]+|/' '{print $3}' | grep -v ^127.0.0 | tr '\n' ' '
It works well when I run it from the bash. Now I created a crontab entry and am hoping to output the ip address to a tmp file:
* * * * * /root/ipv4.sh >> /tmp/tmp.txt
There is nothing written to /tmp/tmp.txt, though the /tmp/tmp.txt is touched every minute. It happens only on Cent OS, while on Ubuntu it works as expected.
Problem solved by changing ip to /sbin/ip in the script.
Related
I want to check how many active meetings there are on the BBB server at any one time from the command line. I have tried
$ bbb-conf --network
but not getting anywhere. I have also checked the number of active connections to port 80 and 443
$ netstat -anp | grep :443 | grep ESTABLISHED | wc -l
but I'm not sure if I can trust that figure.
I know I can use the isMeetingRunning call from the API but I'm just looking for command line.
Any ideas would be appreciated
The following bash script, which can be run from command line on the same machine as the BigBlueButton server, will process the response to the BBB API getMeetings call.
#!/bin/bash
APICallName="getMeetings"
APIQueryString=""
X=$( bbb-conf --secret | fgrep URL: )
APIEndPoint=${X##* }
Y=$( bbb-conf --secret | fgrep Secret: )
Secret=${Y##* }
S=$APICallName$APIQueryString$Secret
Checksum=$( echo -n $S | sha1sum | cut -f 1 -d ' ' )
if [[ "$APIQueryString" == "" ]]
then
URL="${APIEndPoint}api/$APICallName?checksum=$Checksum"
else
URL="${APIEndPoint}api/$APICallName?$APIQueryString&checksum=$Checksum"
fi
wget -q -O - "$URL" | grep -o '<meetingID>' | wc -w
Tested on a live BBB machine.
Note:
The APICallName and APIQueryString can be modified to provide interface to other BBB API calls. See https://docs.bigbluebutton.org/dev/api.html
The command-line sha1sum will output a different result if a newline is appended to its input. This is the reason echo -n is used instead of echo.
In the last line, the script processes the XML output from the API call in a very naïve way, simply counting the number of occurences of the <meetingID> tag. More elaborate processing would probably require parsing the XML.
i would like to do some process, that will block some IP that stores in variables. The syntax that i wrote:
[status4,cmdeks2] = system("sudo tail -1 /var/log/apache2/access.log | cut -d ' ' -f 1");
lm = system(['sudo iptables -A INPUT -s' cmdeks ' -j DROP '])
the cmdeks 2 itself is some IP:
192.168.88.10
But it return some error, that matlab output:
/bin/bash : line 1: -j: command not found
How do i put that cmdeks in the system syntax?
I guess it is because cmdeks2 contains a line feed code and the iptables command breaks by the line feed code.
Extracting only IP address via sscanf will work.
[status4,cmdeks2] = system("tail -1 ./access.log | cut -d ' ' -f 1");
cmdeks2 = sscanf(cmdeks2, '%s\n'); % cmdeks2 contains only IP address
lm = system(['sudo iptables -A INPUT -s ' cmdeks2 ' -j DROP '])
Also, you might have extra iptables rules by your previous trials, so please delete those rules by "iptables -D" command.
I'm trying to identify what application is running on port 56474 without having root access. I know the application was started by me.
Example:
netstat -tunap
tcp 0 0 0.0.0.0:56474 0.0.0.0:* LISTEN -
I've tried using /proc/pid scripts to walk all using grep on ls -l /proc/pid/fd results. Here is my attempt. NOTE: Not sure if I was heading the right direction
for I in `find /proc/*/fd -exec ls -l {} \; 2>/dev/null | awk -F"->|:" '/socket/ {print $4}' | sort -u | sed -e 's/\[//g' -e 's/\]//g'`; do grep $I /proc/*/net/tcp; done
I had no success. Not sure if there is a way. Thanks.
NOTE: Added another answers as lsof was not satisfactory.
This should work:
#! /bin/bash
port=56474
hex_port=$(echo "obase=16; $port" | bc )
inode=$(cat /proc/net/tcp | grep ":$hex_port" | awk '{print $10}')
for i in $(ps axo pid); do
ls -l /proc/$i/fd 2> /dev/null | grep -q ":\[$inode\]" && echo $i
done
Explanation:
Once we have the port number converted to Hexadecimal, we can get the inode number from /proc/net/tcp (10th field), then we loop through /proc/pids/fd and find a symlink pointing to the inode.
If you're sure the application was started by you then you can use lsof:
/usr/sbin/lsof -nP | grep :56474 | awk '{print $2}'
Another technique to resolve pids and ports of all running apps without root:
1.) Get the pids of running apps. Either use the ActivityManager or parse a ps console output.
2.) iterate through /proc/$pid/net/status files and get the matching uid for a pid.
cat /proc/*pid*/net/status | grep Uid:
3.) Call and parse the output of tcp, tcp6,udp, udp6 files to match ports and uids:
cat /proc/net/tcp
...
4.) match the uids of both matchings, get a port-to-pid map without su access.
Cheers,
goethe
I am working on a script that will need to determine which node a db being used by a local app is running on. I've been trying to use this as a chance to force myself to learn awk/sed and have a test script to test the statements. It's working off a copy of the tnsnames.ora file I have moved to the home folder the script is located in.
Here is a valid tnsnames.ora stanza:
(
DESCRIPTION = (
ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP) (Host=iplab)(Port=1521))
)
(CONNECT_DATA=(SID=spurs1))
)
After doing some research and getting the awk expression to pull the tns entry to $host I came up with the below script but it doesn't seem to work.
#!/bin/ksh
db=spurs
host=$(awk -v db=$db "/${db}/ {for(i=1; i<=5; i++) {getline; print}}" tnsnames.ora)
echo $host
host= $host | sed 's/Host\s=\s\([a-z]+[0-9]?\)/\1/'
echo $host
When I run it the awk statement I get the following:
(DESCRIPTION = (ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP) (Host=hostname)(Port=1521))) (CONNECT_DATA=(SID=spurs1)) )
./tns.ksh: line 6: (DESCRIPTION: not found
(DESCRIPTION = (ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP) (Host=hostname)(Port=1521))) (CONNECT_DATA=(SID=spurs1)) )
From what I have seen reading tutorials and forums I think sed is setup correctly and should be setting $host to one or more lowercase letters followed by 0 or 1 numbers after Host = . Since (DESCRIPTION is the start of $host before and after the sed statement I'm not sure how it isn't finding it, an
This worked for me:
tnsping $db | grep HOST | cut -d\ -f 14 | sed 's/).*//g'
On my system I can use this to get the host as long as the host name doesn't have an equals sign (or the actual literal word HOST in the name of the host):
echo $TNS_STRING | sed 's/.HOST//g' | sed 's/).//g' | sed 's/=//g' | sed 's/\s*//g'
Your value for $host is likely a multiline value, so you need to quote it anyplace you use it, i.e.
host=$(awk -v db=$db "/${db}/ {for(i=1; i<=5; i++) {getline; print}}" tnsnames.ora)
echo "$host"
You also need to capture the output (using command-substitution) via $(...)
host=$(echo "$host" | sed 's/Host\s=\s\([a-z]+[0-9]?\)/\1/')
echo "$host"
(and echo it), so it can be processed by sed
Revise
host=$(echo $host | sed 's/.*Host=//; s/).*$//)
echo "$host"
I've switched back to just $host, without the dbl-quotes, as you don't want the linebreaks in the data. Now it is all one big string, and the regex, strips every upto host=, and then strips everything after the first remaining ) char.
If you still get error messages, I don't have access to a tnsnames.ora record, so please edit your query to include a valid record.
I hope this helps.
you may be better relying on the output of tnsping instead of parsing the file: tnsping appears to emit the description on one line:
host=$(
tnsping $db | while read line; do
if [[ "$line" == *HOST* ]]; then
s=${line#*HOST=}; s=${s%%)*}; echo "$s"; break
fi
done
)
This might work for you:
db=spurs
host=$(sed '/^(/,/^)/!d;/^(/{h;d};H;/^)/!d;g;/'"$db"'/!d;s/.*Host=\([^)]*\).*/\1/' tnsnames.ora)
Tested Code:
OIFS=$IFS;
IFS="(";
tns=`tnsping TNS_ALIAS`
tns_arr=($tns);
tns_info=(`(for ((i=0; i<${#tns_arr[#]}; ++i)); do echo "${tns_arr[$i]/)/}"; done)| grep 'HOST\|PORT'|sed 's/)//g'|sed 's/ //g'`)
for ((i=0; i<${#tns_info[#]}; ++i)); do eval "export ${tns_info[$i]}"; done
echo "host:" $HOST
echo "port:" $PORT
IFS=$OIFS;
Some commands in Solaris (such as iostat) report disk related information using disk names such as sd0 or sdd2. Is there a consistent way to map these names back to the standard /dev/dsk/c?t?d?s? disk names in Solaris?
Edit: As Amit points out, iostat -n produces device names such as eg c0t0d0s0 instead of sd0. But how do I found out that sd0 actually is c0t0d0s0? I'm looking for something that produces a list like this:
sd0=/dev/dsk/c0t0d0s0
...
sdd2=/dev/dsk/c1t0d0s4
...
Maybe I could run iostat twice (with and without -n) and then join up the results and hope that the number of lines and device sorting produced by iostat is identical between the two runs?
Following Amit's idea to answer my own question, this is what I have come up with:
iostat -x|tail -n +3|awk '{print $1}'>/tmp/f0.txt.$$
iostat -nx|tail -n +3|awk '{print "/dev/dsk/"$11}'>/tmp/f1.txt.$$
paste -d= /tmp/f[01].txt.$$
rm /tmp/f[01].txt.$$
Running this on a Solaris 10 server gives the following output:
sd0=/dev/dsk/c0t0d0
sd1=/dev/dsk/c0t1d0
sd4=/dev/dsk/c0t4d0
sd6=/dev/dsk/c0t6d0
sd15=/dev/dsk/c1t0d0
sd16=/dev/dsk/c1t1d0
sd21=/dev/dsk/c1t6d0
ssd0=/dev/dsk/c2t1d0
ssd1=/dev/dsk/c3t5d0
ssd3=/dev/dsk/c3t6d0
ssd4=/dev/dsk/c3t22d0
ssd5=/dev/dsk/c3t20d0
ssd7=/dev/dsk/c3t21d0
ssd8=/dev/dsk/c3t2d0
ssd18=/dev/dsk/c3t3d0
ssd19=/dev/dsk/c3t4d0
ssd28=/dev/dsk/c3t0d0
ssd29=/dev/dsk/c3t18d0
ssd30=/dev/dsk/c3t17d0
ssd32=/dev/dsk/c3t16d0
ssd33=/dev/dsk/c3t19d0
ssd34=/dev/dsk/c3t1d0
The solution is not very elegant (it's not a one-liner), but it seems to work.
One liner version of the accepted answer (I only have 1 reputation so I can't post a comment):
paste -d= <(iostat -x | awk '{print $1}') <(iostat -xn | awk '{print $NF}') | tail -n +3
Try using the '-n' switch. For eg. 'iostat -n'
As pointed out in other answers, you can map the device name back to the instance name via the device path and information contained in /etc/path_to_inst. Here is a Perl script that will accomplish the task:
#!/usr/bin/env perl
use strict;
my #path_to_inst = qx#cat /etc/path_to_inst#;
map {s/"//g} #path_to_inst;
my ($device, $path, #instances);
for my $line (qx#ls -l /dev/dsk/*s2#) {
($device, $path) = (split(/\s+/, $line))[-3, -1];
$path =~ s#.*/devices(.*):c#$1#;
#instances =
map {join("", (split /\s+/)[-1, -2])}
grep {/$path/} #path_to_inst;
*emphasized text*
for my $instance (#instances) {
print "$device $instance\n";
}
}
I found the following in the Solaris Transistion Guide:
"Instance Names
Instance names refer to the nth device in the system (for example, sd20).
Instance names are occasionally reported in driver error messages. You can determine the binding of an instance name to a physical name by looking at dmesg(1M) output, as in the following example.
sd9 at esp2: target 1 lun 1
sd9 is /sbus#1,f8000000/esp#0,800000/sd#1,0
<SUN0424 cyl 1151 alt 2 hd 9 sec 80>
Once the instance name has been assigned to a device, it remains bound to that device.
Instance numbers are encoded in a device's minor number. To keep instance numbers consistent across reboots, the system records them in the /etc/path_to_inst file. This file is read only at boot time, and is currently updated by the add_drv(1M) and drvconf"
So based upon that, I wrote the following script:
for device in /dev/dsk/*s2
do
dpath="$(ls -l $device | nawk '{print $11}')"
dpath="${dpath#*devices/}"
dpath="${dpath%:*}"
iname="$(nawk -v dpath=$dpath '{
if ($0 ~ dpath) {
gsub("\"", "", $3)
print $3 $2
}
}' /etc/path_to_inst)"
echo "$(basename ${device}) = ${iname}"
done
By reading the information directly out of the path_to_inst file, we are allowing for adding and deleting devices, which will skew the instance numbers if you simply count the instances in the /devices directory tree.
I think simplest way to find descriptive name having instance name is:
# iostat -xn sd0
extended device statistics
r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b device
4.9 0.2 312.1 1.9 0.0 0.0 3.3 3.5 0 1 c1t1d0
#
The last column shows descriptive name for provided instance name.
sd0 sdd0 are instance names of devices.. you can check /etc/path_to_inst to get instance name mapping to physical device name, then check link in /dev/dsk (to which physical device it is pointing) it is 100% sure method, though i dont know how to code it ;)
I found this snippet on the internet some time ago, and it does the trick. This was on Solaris 8:
#!/bin/sh
cd /dev/rdsk
/usr/bin/ls -l *s0 | tee /tmp/d1c |awk '{print "/usr/bin/ls -l "$11}' | \
sh | awk '{print "sd" substr($0,38,4)/8}' >/tmp/d1d
awk '{print substr($9,1,6)}' /tmp/d1c |paste - /tmp/d1d
rm /tmp/d1[cd]
A slight variation to allow for disk names that are longer than 8 characters (encountered when dealing with disk arrays on a SAN)
#!/bin/sh
cd /dev/rdsk
/usr/bin/ls -l *s0 | tee /tmp/d1c | awk '{print "/usr/bin/ls -l "$11}' | \
sh | awk '{print "sd" substr($0,38,4)/8}' >/tmp/d1d
awk '{print substr($9,1,index($9,"s0)-1)}' /tmp/d1c | paste - /tmp/d1d
rm /tmp/d1[cd]