Table of Contents
Search for available packages
root@server01:~# apt-cache search isc-dhcp isc-dhcp-client - ISC DHCP client isc-dhcp-client-dbg - ISC DHCP client (debugging symbols) isc-dhcp-common - common files used by all the isc-dhcp* packages ...edited...
Install available package
root@server01:~# apt-get install tree Re ading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed tree 0 to upgrade, 1 to newly install, 0 to remove and 2 not to upgrade. Need to get 28.4 kB of archives. After this operation, 102 kB of additional disk space will be used. Get:1 http://gb.archive.ubuntu.com/ubuntu/ precise/universe tree amd64 1.5.3-2 [28.4 kB] Fetched 28.4 kB in 0s (834 kB/s) Selecting previously unselected package tree. (Reading database ... 55136 files and directories currently installed.) Unpacking tree (from .../tree_1.5.3-2_amd64.deb) ... Processing triggers for man-db ... Setting up tree (1.5.3-2) ... root@server01:~#
List installed packages
root@server01:~# dpkg --get-selections | grep -v deinstall | grep dhcp isc-dhcp-client install isc-dhcp-common install root@server01:~#
Show version of packages installed
root@server01:/# dpkg -l | grep openssl ii openssl 1.0.1-4ubuntu5.12 Secure Socket Layer (SSL) binary and related cryptographic tools ii python-openssl 0.12-1ubuntu2.1 Python wrapper around the OpenSSL library root@server01:/b#
root@server01:/# dpkg -p openssl Package: openssl Priority: optional Section: utils Installed-Size: 901 Maintainer: Ubuntu Developers <email@example.com> Architecture: amd64 Version: 1.0.1-4ubuntu5.12 Depends: libc6 (>= 2.15), libssl1.0.0 (>= 1.0.1) Suggests: ca-certificates Size: 523340 Description: Secure Socket Layer (SSL) binary and related cryptographic tools This package contains the openssl binary and related tools. . It is part of the OpenSSL implementation of SSL. . You need it to perform certain cryptographic actions like: - Creation of RSA, DH and DSA key parameters; - Creation of X.509 certificates, CSRs and CRLs; - Calculation of message digests; - Encryption and decryption with ciphers; - SSL/TLS client and server tests; - Handling of S/MIME signed or encrypted mail. Original-Maintainer: Debian OpenSSL Team <firstname.lastname@example.org> root@server01:/#
Delete installed package
- apt-get remove packagename
will remove the binaries, but not the configuration or data files of the package packagename. It will also leave dependencies installed with it on installation time untouched.
- apt-get purge packagename or
- apt-get remove –purge packagename
will remove about everything regarding the package packagename, but not the dependencies installed with it on installation. Both commands are equivalent.
Particularly useful when you want to 'start all over' with an application because you messed up the configuration. However, it does not remove configuration or data files residing in users home directories, usually in hidden folders there. There is no easy way to get those removed as well.
- apt-get autoremove
removes orphaned packages, i.e. installed packages that used to be installed as an dependency, but aren't any longer. Use this after removing a package which had installed dependencies you're no longer interested in.
root@server01:~# apt-get remove isc-dhcp-client isc-dhcp-common Reading package lists... Done Building dependency tree Reading state information... Done The following packages will be REMOVED isc-dhcp-client isc-dhcp-common ubuntu-minimal 0 to upgrade, 0 to newly install, 3 to remove and 2 not to upgrade. After this operation, 1,498 kB disk space will be freed. Do you want to continue [Y/n]? y (Reading database ... 55173 files and directories currently installed.) Removing ubuntu-minimal ... Removing isc-dhcp-client ... Removing isc-dhcp-common ... Processing triggers for man-db ... root@server01:~#
Show files in package
root@server01:~# dpkg-query -L hp-health /. /var /var/log /var/log/hp-health /var/spool /var/spool/hp-health /var/spool/compaq
Update single package only
Such as bash regarding shellshock vulnerability.
root@server01:~# apt-get install --only-upgrade bash Reading package lists... Done Building dependency tree Reading state information... Done Preparing to replace bash 4.2-2ubuntu2.1 (using .../bash_4.2-2ubuntu2.3_amd64.deb) ...
Force apt traffic through a proxy server
This situation arose in AWS where there was a private subnet (10.100.250.0) which could not route out to the internet. The solution was to install a proxy running squid. APT needs configuring to use this proxy, it is a line in
root@server01:~# cat /etc/apt/apt.conf Acquire::http::Proxy "http://10.10.10.11:8080";
It may be advantageous to set assuming your proxy is 10.10.10.11:-
export https_proxy=https://10.10.10.11:8080 export http_proxy=http://10.10.10.11:8080
Apt-Pinning the packages
In some cases you might need to “pin” the selected packages to avoid the upgrades from the distribution repositories. You’ll need to make a new file /etc/apt/preferences.d/00ServiceName.pref and add the following lines in it, for example:-
Package: * Pin: release o=Percona Development Team Pin-Priority: 1001
For more information about the pinning you can check the official debian wiki.
GPG error: Verification problem
Error during an apt-get update is:-
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://apt.puppetlabs.com precise Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7F438280EF8D349F
Fix is to import the key:-
root@server01:~# apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 7F438280EF8D349F Executing: gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /tmp/tmp.LMTlTPOSLE --trustdb-name /etc/apt/trustdb.gpg --keyring /etc/apt/trusted.gpg --primary-keyring /etc/apt/trusted.gpg --keyring /etc/apt/trusted.gpg.d//puppetlabs-keyring.gpg --keyring /etc/apt/trusted.gpg.d//puppetlabs-nightly-keyring.gpg --keyserver keyserver.ubuntu.com --recv-keys 7F438280EF8D349F gpg: requesting key EF8D349F from hkp server keyserver.ubuntu.com gpg: key EF8D349F: public key "Puppet, Inc. Release Key (Puppet, Inc. Release Key) <email@example.com>" imported gpg: no ultimately trusted keys found gpg: Total number processed: 1 gpg: imported: 1 (RSA: 1) root@server01:~#
Force Remove packages
To remove a package causing an unworkable dependency loop, use this, but beware it may break your system.
-r removes a package,
-P purges any left over config files too, they are mutually exclusive:-
[root@server ~]# dpkg -r --force-depends <package_name> [root@server ~]# dpkg -P --force-depends <package_name>