Unix OS





Unix is a multitasking, multi-user computer operating system originally developed in 1969 at Bell Labs. Today, it is a modern OS with many commercial flavors and licensees, including FreeBSD, Hewlett-Packard’s UX, IBM AIX and Apple Mac OS-X. Apart from its command-line interface, most UNIX variations support the standardized X Window System for GUIs, with the exception of the Mac OS, which uses a proprietary system.

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what is difference between below commands

$ cd xyz

it says no such file or directory

$ cd /xyz
says no such file or directory

where as when i say

$ cd /xyz/
it goes to xyz directory though

what is use or importance of /  and / at the beginning and end?

please advise
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Hi Guys,

I would like to have a opensource software to perform following tasks on zimbra.

zimbra logging
per user email send receive count per day, week, month & year.
access log success & failure & Etc..

any help greatly appreciated.
thank you.
For patching I used Tanium before on cross platforms environment.  Multiple OSs: MS, unix, mac.  Unfortunately Tanium only serves for a very large customers.  What would be an alternatives to Tanium?  
I heard Kace from Quest is great and easy to deploy with VM or an Appliance?  
HQ in US.  About 4-5 international offices.
About 400 hosts on Win, Mac, ubuntu.

Thanks in advance!
Does anyone on here have any experience auditing Mac OSX and MacOS laptops specifically for PCI Compliance? If so, how did you end up logging from them to a centralized server and what did you use? I am attempting to use OSSEC to pull the logs from /var/audit/current but would /var/etc/com.apple.authd be better? Or /var/log/system.log?) The purpose of this is to satisfy PCI DSS req. 10.2.2, 10.1.5. If I use OSSEC will I need to create a custom decoder for OSSEC for using the praudit command on /var/audit/current?
The maxage setting on an Aix server has been set to 4 but the server never prompts for a password reset after 4 weeks, Infact the server has never prompted for a password since the first time I have logged into the server which is more than 200 days
Interestingly enough I have no problem using let's encrypt on Windows platform and figured it was going to be a breeze on *nix... Running into a slew of issues.  For one I am trying to use certbot to facilitate this.  When I issue the correct commands and webroot I see it builds the .well-known folder but it does not build the acme-challenge folder.  If I try to manually create the acme-challenge folder it deletes it after the sudo certbot certonly --webroot -w /var/www/example -d example.com -d www.example.com command (with my domain info substituted of course) with the following error:

Detail: Invalid response from
   <title>403 Forbidden</title>
Super frustrated as everything in *nix is always easier, right?  Well not this time LOL.   Any suggestions would be appreciated!


  I would like to know if there is a way to create a Symlink-like file but with the difference that the file it points to gets executed when the link is read and the output is what I get from reading it.
  It should work on freebsd/linux.


Best regards
I about 10 yrs back, there are CIS tools that we could download for free
that will flag out the date of the last OS patches.

Are these tools still available for free download & what's the URL?

Without these tools, how can we check in an OS (Windows 2008 R2, Win 2012,
Solaris 10 & 11,  AIX 6.1 & 7.1) , the date of the latest patches applied in the
I have installed 2 different IDM Ultrium-TD3 tape drives and in the 2nd case, I have ALSO installed the lin_tape and lin_taped (daemon).  I also have sg3_utils 1.42, built from source - all this are on x86_64 bit computers.

Many of the commands work, including sg_read_buffer for reading the cartridge memory.

The problem is, commands such as sg_read_attr/sg_write_attr (ioctl 0x8D, 0x8C) whether from a normal C program or from the sg approach, do not ever allow reading or writing the attributes - instead, it leads to an error, such as:

SG_WRITE_ATT_0803 command error: Host_status=0x05 [DID_ABORT]
Error : Write failed (try verbose opt)

I can try either generic /dev devices or /dev/IBM types of devices.  Each gives an error.  In one case, I have an idea for how to try to fix it, but I'm just wondering, is the firmware (mine is 6B20) just not implementing it?  I doubt that's the problem.  I can upload the firmware as hex code but I would like to see the source.

Also, I don't know whether or not running lintape/lintaped matters and whether or not the IBM-generic/IBM-specific/sg-generic drivers are the issue.  I'm trying to pin down what approach to go on next.  There are literally three sets of drivers.  And I don't know whether or not I should install Tivoli.

Given all the variables, I just want to know how to proceed to get to a working sg_read_attr/sg_write_attr command.  I even tried to start with the lowest numbered attribute.

I have also tried external …
My SCO Unix RAID 5 server have 3 HDD. Today 1st and 2nd HDD failed only 3rd HDD showing ONLINE. Is there any chance of data recovery if i install new HDD in 1 and rebuild and then the 2nd HDD and rebuild.
Is there any chance of data recovery.
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In putty vi editor vi unix how to see later pages and change colors for bettwer view.

i open big property file not able to see what is at bottom.

how to search in vi editor for some text sat xyz.

setting i went i changed colors , font etc not reflecting.

what is best setting to give for better view

when i opened
abc.properties in vi
it says 536L, 28390C
what is L what is C
how to know how many lines there how many it is showing etc
can i use winscp free version for production servers viewing property files?
please advise

I am fed up with putty with basic options.

Any better tools or IDEs to check logs or to grep unix/linux boxes.

Where  i can download secure ftp and how much is fees?
any advanced putty IDE there
any good free IDE accepted by industry.

please advise
We have some alarms lights  in the front of the server panel.  How could i get a diagnostic list of all the current failures in the server.  Please provide detail steps.
I run cat /dev/null /var/adm/lastlog and recovered space under FS but /var still showing pretty high, this is happening in Solaris 10 global zone.

Please advise how to recover space under /var in this case or do I need to restart some daemon to reclaim space under /var. Please reply.
what the heck is delta rpm and why use it , cant I just update or upgrade with yum update or something like that ?

Hi gurus,

I have AIX (7100-04-04-1717) lpar with installed following packets:
bos.cifs_fs.rte     C     F    Runtime for SMBFS
bos.cifs_fs.smit     C     F    SMIT Interface for SMBFS

This lpar was successfully mounting share on W2k8 R2 until recently change on windows server. Change on windows side was disabling smbv1 protocol. Since then, there is no way to mount this share again. I have asked my colleagues to turn smbv1 back on, until I figure out how to solve this. When they turn smbv1 protocol  on, I can mount the share again. IBM does not provide any support for cifs, and I can't find any official document claiming that this client can't be used for higher smb protocols than smbv1.

I even installed samba 4.1 on AIX, and with smbclient tool I can connect to windows share forcing higher protocol versions ( -m SMB3), but this is not a solution, because I must have permanent file system mounted on aix. So this is not a valid solution.  
Does anyone have a  idea on how to solve this, or any link to official documentation which I can use to prove that this is not supported?
Or if I am trying something in wrong way , please let me know.
Thanks in advance,
Hi expert

How to upload SSL to openLdap server?
Hello All,

I am in a situation to push database audit XML logs to syslog server. Audit logs are getting generated when Audit_Trail is set to OS. The same is not happening when Audit_Trail is set to XML,EXTENDED. Please advice on this.

SQL> select banner from v$version;

Oracle Database 10g Enterprise Edition Release - Prod
PL/SQL Release - Production
CORE      Production
TNS for Linux: Version - Production
NLSRTL Version - Production

SQL> show parameter audit
NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
audit_file_dest                      string      /u01/appldrch/DRCH_DB_audit_lo
audit_sys_operations                 boolean     TRUE
audit_syslog_level                   string      LOCAL1
audit_trail                          string      XML, EXTENDED

[root@appsdr ~]# cat /etc/syslog.conf
local1.warning /var/log/audit.log

Thank You.

John Marshal.A
We hvae created new policy to check particular vulnerabikity in unix. We have enabled all the required plugins however scan doesnt discovered the host even. So looking what are the other mandatory/ dependent plugins need to enable.
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I have xlc compiler version 8 and perl 5.10 running on AIX 7.1. I have been able to install DBI.pm module successfully, but now am in need to install DBD::ORACLE module. The oracle version is 12 (64bit)

perl Makefile.PL runs fine for the DBD::ORACLE module, however the "make" command is throwing below error:
I attempted to fix the issue by changing the object mode value, but that end up giving a different type of error.
Can you advise on the solution ?

        rm -f blib/arch/auto/DBD/Oracle/Oracle.so
        LD_RUN_PATH="/u01/app/oracle/product/12.1.0/client_1/lib:/u01/app/oracle/product/12.1.0/client_1/rdbms/lib" ld  -bhalt:4 -G -bI:/usr/opt/perl5/lib/5.10.1
            /aix-thread-multi/CORE/perl.exp -bE:Oracle.exp -bnoentry -lpthreads -lc -lm -L/usr/local/lib Oracle.o  dbdimp.o  oci8.o /lib/crt0_64.o -bI:/usr/lib/iocp.
            exp  -o blib/arch/auto/DBD/Oracle/Oracle.so     -L/u01/app/oracle/product/12.1.0/client_1/lib/ -lclntsh -lclntshcore -lld -lm -ldl -lc -lm -lpthreads -
            -lbsd_r -lld -lperfstat -lm -lpthreads
ld: 0711-736 ERROR: Input file /lib/crt0_64.o:
        XCOFF64 object files are not allowed in 32-bit mode.
make: The error code from the last command is 8.

#bootinfo -K

#ORACCENV='cc=xlc_r'; export ORACCENV

#export OBJECT_MODE=64
        rm -f blib/arch/auto/DBD/Oracle/Oracle.so
        LD_RUN_PATH="/u01/app/oracle/product/12.1.0/client_1/lib:/u01/app/oracle/product/12.1.0/client_1/rdbms/lib" ld  -bhalt:4 -G …
I recently upgraded AIX from 6.1 to 7.1, which resulted in perl getting upgraded from 5.8 to 5.10 as well and in process i no longer have a dbi.pm module under perl 5.10.

I have been unable to find binary version for dbi.pm for perl 5.10 so i am trying to compile it but running into an issue with it.
I am using steps of running perl Makefile.PL, make, make test, make install to compile.
I am able to successfully run perl Makefile.PL from the dbi.pm directory that i saved in /tmp from cpan.org, but when i run the "make" command, i get following error.

Skip blib/lib/DBI/ProfileData.pm (unchanged)
        xlc_r -q32 -c    -D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=-1 -qnoansialias -DUSE_NATIVE_DLOPEN -DNEED_PTHREAD_INIT -qlanglvl=extended -I/usr/local/include -q32 -D_LARGE_FILES -qlonglong -O    -DVERSION=\"1.636\"  -DXS_VERSION=\"1.636\"  "-I/usr/opt/perl5/lib/5.10.1/aix-thread-multi/CORE"   Perl.c
/bin/sh: xlc_r:  not found
make: The error code from the last command is 127.

I do have xlc compiler installed.
  vac.C              COMMITTED  IBM XL C Compiler
  vac.C              COMMITTED  IBM XL C Compiler
  vacpp.cmp.core     COMMITTED  IBM XL C/C++ Compiler
  vacpp.cmp.core     COMMITTED  IBM XL C/C++ Compiler
  xlC.aix61.rte     COMMITTED  IBM XL C++ Runtime for AIX 6.1

/usr/vacpp/bin/xlC -qversion
IBM XL C/C++ Enterprise Edition V8.0 for AIX
Version: …
I want to send all my TSM events like backup failure, backup missed, scheduler stopped, and all other TSM warning and critical errors to be sent to HP monitoring solution. So that HP can get the TSM error or warning and raise ticket aromatically.

Please send me step by step procedure to configure n enable the same.

Since I m very new to Unix. Please send me easy/details to configure n enable TSM app alert.

Thanku very much
In advance

I have installed a module on the puppet master server,  how do I make client to pickup those modules and execute?
I have a file with a character that translates into 272 when I do:
od -xc

The character looks like an A with a caret on top with a degree sign to the right. I am attaching an image of the character as well. I have tried sed, perl and tr and none of them are working.

For example:
sed -e 's/'$(echo "272")'/ /g' input_file > output_file

This does not work.

Any suggestions?
I am creating a shell script to check if cron jobs are enabled/disabled and send a mail notification for the same (with job name).


crontab -l > /app/file.txt

while IFS= read -r value; do
entry=`$value | awk '{print $1}'`
echo $entry
if [[ $entry == "#" ]]
  echo " Entry $value is disabled "
elif [[ $entry == '#*' ]]
   echo " Entry $value is disabled "
   echo " Entry $value is enabled "
done < $ctab

Open in new window

However, the above code is failing with the error message (#*: command not found).

Unix OS





Unix is a multitasking, multi-user computer operating system originally developed in 1969 at Bell Labs. Today, it is a modern OS with many commercial flavors and licensees, including FreeBSD, Hewlett-Packard’s UX, IBM AIX and Apple Mac OS-X. Apart from its command-line interface, most UNIX variations support the standardized X Window System for GUIs, with the exception of the Mac OS, which uses a proprietary system.