SSH password less log-in problem

Machine1: re-solx86 (A Solaris x86 machine)
Machine2: vm-rh21-lager (A RHEL machine)

Requirement: Need to establish a password less login from Machine2 -> machine1

Solution:
Login machine1 -> machine2
1) Created RSA keys by running command "ssh-keygen -t rsa" on Machine1
2) Added content of "id_rsa.pub" file from machine1 to the file "authorized_keys" in machine2
Login from machine1 -> machine2 is success

Login machine2 -> machine1
1) Added content of "id_rsa.pub" file from machine2 to a file "authorized_keys" in machine1
Login from machine2 -> machine1 still asking for password.

Problem: Permissions of ~/.ssh directory in machine1 is 755. ssh won't work if permission of ~/.ssh is other than 700.
Solution: Changed permission of ~/.ssh to 700, now it is successful

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ESP package manager

EPM (ESP package manager), is the second package manager, which I used. In my previous organization Synopsys, I used Synopsys Installer, which is an internal package management tool used only in Synopsys. But it is good to know EPM is a free package manager developed by Easy software products.

The design goal of EPM is to solve the problem of software distribution with Unix/Linux OS. The problem is every OS supports it's own packaging tools and each has unique requirements for the software development environment. EPM provides solution to this problem by providing it's own portable distribution format and also vendor specific formats like rpm, depot, dpkg, pkgadd, etc. This allows you to build software distribution files for any OS from the same sources.

You can download EPM from http://www.epmhome.org/ and the EPM book at http://www.epmhome.org/documentation.php teaches you how to use EPM.

EPM requires few pre-installed softwares. They are C compiler, make utility, Bourne (or Korn or bash) shell and gzip. The optional Graphical setup program requires a C++ compiler, FLTK library. End user systems require Bourne shell, df, tar & gzip utilities to install portable distributions.

Basically EPM reads one or more software list files that describe a single software package. These list files needs to be written in specific format, Chapter 3 of EPM book explains it in detail.

To build a software package, epm program is used. For example to build a portable software package for an application called foo, type the following command
epm foo
This expects a list file by name foo.list. If your list file is created with different name, then you can mention the list file name by command line argument as
epm foo base.list

You can install the portable packages by calling an installation script product.install where product is the name of the package.
cd os-release-arch
./product.install
After answering few yes/no questions, product will be installed.

To create vendor specific packages use -f option
epm -f rpm foo base.list

EPM also supports preinstall, postinstall, prepatch, postpatch, preremove & postremove scripts. These scripts are bourne shell scripts, needs to be called from list file
It also supports init scripts and also patch software distributions.

For detailed usage refer EPM book at http://www.epmhome.org/documentation.php

Enjoy building software packages with EPM ..... :)

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HP UX start/stop/restart sshd service

To start/stop sshd service, you must use "root" account"

System startup configuration file

/etc/rc.config.d/sshd

Stop HP UX SSH Service

/sbin/init.d/secsh stop


Start HP UX SSH Service

/sbin/init.d/secsh start


If /sbin/init.d/secsh is not found, you can try the following if found

/sbin/init.d/S91sshd start

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Unix Operating System Name Abbreviations and Processor Architecture Abbreviations

Operating System Name Abbreviations

Operating System	Name
AIX	aix
Compaq Tru64 UNIX Digital UNIX OSF/1	tru64
FreeBSD	freebsd
HP-UX	hpux
IRIX	irix
Linux	linux
MacOS X	macosx
NetBSD	netbsd
OpenBSD	openbsd
Solaris	solaris

Processor Architecture Abbreviations

Processor(s)	Abbreviation
Compaq Alpha	alpha
HP Precision Architecture	hppa
INTEL 80x86	intel
INTEL 80x86 w/64bit Extensions	x86_64
MIPS RISC	mips
IBM Power PC	powerpc
SPARC MicroSPARC UltraSPARC	sparc

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Software Packaging Formats

Software Packaging Formats (Reference - s/w distribution using ESP)
In Unix there are many open source packaging systems, it is always better to have a list and to compare among them.

Format	Operating Systems1	Binaries	Cross- Platform	Patches	Up- grades	Con- flicts	Re- quires	Re- places	Config Files	Map Files	Un- install
installp	AIX	Yes	No	No	No	Yes	Yes	No	No	No	Yes
pkg_add	FreeBSD	Yes	Yes2	No	No	No	No	No	No	No	Yes
pkg_add	NetBSD OpenBSD	Yes	Yes2	No	No	Yes	Yes	No	No	No	Yes
dpkg	Corel Linux Debian GNU/Linux	Yes	Yes2	No	Yes	Yes	Yes	Yes	Yes	No	Yes
depot	HP-UX	Yes	No	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes
inst	IRIX	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Install.app	MacOS X	Yes	No	No	Yes	No	No	No	No	No	No
pkgadd	Solaris	Yes	No	Yes	No	Yes	Yes	No	Yes	Yes	Yes
rpm	Mandrake Red Hat SuSE TurboLinux	Yes	Yes2	No	Yes	Yes	Yes	No	Yes	No	Yes
setld	Tru64 UNIX	Yes	No	No	No	Yes	Yes	No	No	No	Yes
slackware	Slackware Linux	Yes	No	No	No	Yes	Yes	No	No	No	Yes

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dpkg-deb (subprocess): control: internal gzip error: read(4096) != write(0): No space left on device

set TMPDIR environment variable to a free disk space path

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How to install Perl modules

For example to install Mail::Mailer module, you can use below
command

perl -MCPAN -e 'install Mail::Mailer'

Also refer http://www.cpan.org/modules/INSTALL.html for another
approach

Offline Installation of Perl module

perl Makefile.PL
make
make test
make install 

How do I find out what modules are already installed on my system?

Each time a module is installed on your system, it appends information like the following to a file called perllocal.pod which can be found in /usr/local/lib/perl5/version number/architecture/ or something akin to that. The path for your specific installation is in your @INC which you can divine with perl -V.
=head2 Wed May 12 13:42:53 1999: C L
=over 4
=item *
C
=item *
C
=item *
C
=item *
C
=back

Each entry includes the Module name, date and time it was installed, where it was installed, linktype [ static or dynamic ], version and executables, if any, included with the module.

Another way to do this is http://vijayk.blogspot.com/2008/06/list-all-installed-perl-modules.html

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