http://www.topdog.za.net/ 2010-09-10T21:07:25-04:00 http://www.topdog.za.net/ http://www.topdog.za.net/lib/images/favicon.ico text/html 2010-08-21T02:34:25-04:00 http://www.topdog.za.net/baruwa Baruwa (swahili for letter or mail) is a web 2.0 MailScanner front-end. It provides an easy to use interface for managing a MailScanner installation. It is used to perform operations such as releasing quarantined messages, spam learning, whitelisting and blacklisting addresses, monitoring the health of the services etc. Baruwa is implemented using web 2.0 features (AJAX) where deemed fit, graphing is also implemented on the client side using SVG, Silverlight or VML. text/html 2008-08-17T12:23:37-04:00 http://www.topdog.za.net/centos_5_cisco_lab Background I recently decided to study for the Cisco CCSP certification. My main concern in the beginning was the fact that most of the lab simulation software that i found out there could only run on Windows, this was a problem for me given the fact that i do not own a windows computer. text/html 2008-02-06T04:41:58-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_apache_setup Disable modules We will disable some modules that we are not using thus freeing up memory and also improving security. * Edit /etc/httpd/conf/httpd.conf and comment out the modules as below. #LoadModule ldap_module modules/mod_ldap.so #LoadModule authnz_ldap_module modules/mod_authnz_ldap.so #LoadModule dav_module modules/mod_dav.so #LoadModule status_module modules/mod_status.so #LoadModule dav_fs_module modules/mod_dav_fs.so #LoadModule proxy_module modules/mod_proxy.so #LoadModule proxy… text/html 2008-02-09T09:54:55-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_bind_setup Introduction Bind will be setup chrooted to improve security we will also use views to prevent abuse of the dns server. Basic configuration The basic configuration disables by default, recursive queries and zone transfers. We also obscure the version of BIND we are running such that we are not hit by zero day vulnerabilities from script kiddies. text/html 2008-02-07T02:05:50-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_clamav_milter_setup * Edit /etc/sysconfig/clamav-milter CLAMAV_FLAGS=" --config-file=/etc/clamd.conf --force-scan --local --max-children=5 --sendmail-cf= --outgoing --quiet " SOCKET_ADDRESS="local:/var/clamav/clmilter.socket" text/html 2008-02-03T15:10:33-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_dovecot_setup Introduction This will setup dovecot as our IMAP/POP3 server. Basic configuration We will setup dovecot for IMAP and POP3 and disable SSL. protocols = imap pop3 listen = * ssl_listen = * ssl_disable = yes Maildir We will use the maildir format as opposed to the default mbox format. text/html 2008-02-04T00:51:23-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_imapproxy_setup Introduction imapproxy was written to compensate for webmail clients that are unable to maintain persistent connections to an IMAP server. Most webmail clients need to log in to an IMAP server for nearly every single transaction. This behaviour can cause tragic performance problems on the IMAP server. imapproxy tries to deal with this problem by leaving server connections open for a short time after a webmail client logs out. When the webmail client connects again, imapproxy will determine if t… text/html 2008-02-06T04:38:12-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_iptables_setup Introduction This is a basic firewall it may not suit your needs, firewalling is an art so i recommend to read into it to improve on this basic one. Basic config Add these rules in your configuration file /etc/sysconfig/iptables *raw :PREROUTING ACCEPT [0:0] :OUTPUT ACCEPT [0:0] COMMIT *nat :PREROUTING ACCEPT [0:0] :POSTROUTING ACCEPT [0:0] :OUTPUT ACCEPT [0:0] COMMIT *mangle :PREROUTING ACCEPT [0:0] :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] :POSTROUTING ACCEPT [0:0]… text/html 2008-02-05T06:15:09-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_mysql_setup Basic config * listen only to the localhost, edit /etc/my.cnf under the mysqld section bind-address = 127.0.0.1 Set root password * Set the root password # mysqladmin -u root password NEWPASSWORD Start mysql # service mysqld start text/html 2009-05-20T05:55:25-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_postfix_setup Introduction We will be setting up postfix with the following features * Virtual hosting * UCE prevention * Anti virus * SMTP authentication * TLS * RBLs * SPF * Attack mitigation The adding of accounts and domains with be configured through virtualmin although it can be done manually as well. The setup is designed to be resource friendly so should be able to run on machines that are not over spec'ed so enabling the resources to be put to better use. To make it resource frien… text/html 2008-02-07T10:17:04-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_roundcube_setup Create database * Create the database and add the roundcube user. # mysqladmin -p create roundcube # mysql -p # mysql> GRANT ALL ON roundcube.* TO roundcube@localhost IDENTIFIED BY 'password'; * Initialize the database # mysql -u roundcube -p roundcube < /usr/share/doc/roundcube-0.1/SQL/mysql5.initial.sql Basic config * Configure database DSN in /var/www/roundcube/config/db.inc.php text/html 2008-02-03T11:58:35-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_setup This howto is still under development please use with caution. Introduction This tutorial shows how to set up a CentOS 5.x server to offer all services needed by virtual web hosters. These include web hosting,smtp server with (SMTP-AUTH and TLS,SPF,DKIM,Domainkeys),DNS,FTP,MySQL,POP3/IMAP,Firewall,Webalizer for stats. text/html 2008-02-03T12:16:14-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_setup2 * Configure networking Set ip address and netmask Set gateway and dns servers Set the hostname * Set the timezone * Set the root password * Select server group and select customize software selection * Package groups select as follows: * DNS name server * bind-chroot text/html 2008-02-07T10:00:20-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_setup3 Start installation File system is formatted The installation will run Reboot the system Services to disable To enhance security and free system resources on the system we need to disable any services that are not required. You can run this script to do this for you. text/html 2008-05-16T03:16:41-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_setup4 Install webmin / virtualmin * Import webmin pgp key # wget http://www.webmin.com/jcameron-key.asc # rpm --import jcameron-key.asc * Download the rpm # wget http://prdownloads.sourceforge.net/webadmin/webmin-1.390-1.noarch.rpm * Verify the rpm (should say OK or else download again) text/html 2008-02-27T06:37:39-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_setup5 Testing Postfix Test smtp telnet 192.168.1.5 25 Connected to localhost. Escape character is '^]'. 220 tds mail cluster helo me 250 hosting1 mail from:address@yahoo.com 250 2.1.0 Ok rcpt: andrew@example.com 250 2.1.0 Ok DATA 354 End data with <CR><LF>.<CR><LF> From:address@yahoo.com To:andrew@example.com Subject:This is a test Hi This is a test . 250 2.0.0 Ok: queued as 4ACCC7C5A6 text/html 2008-02-03T16:16:22-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_spamass_milter_setup Basic configuration * Edit /etc/sysconfig/spamass-milter SOCKET=/var/run/spamass.sock EXTRA_FLAGS="-m -r 8" Patch We need to patch the init file to fix the permissions of the socket created such that postfix is able to use the socket. # wget http://www.topdog-software.com/files/spamass-milter.patch # patch /etc/rc.d/init.d/spamass-milter < spamass-milter.patch text/html 2008-02-09T09:41:46-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_spamassassin_setup Basic config required_hits 5 report_safe 0 rewrite_header Subject [SPAM] Create mysql database * Create the database # mysqladmin -p create bayes * Populate the database # mysql -p bayes < /usr/share/doc/spamassassin-$(rpm --qf %{VERSION} -q spamassassin)/sql/bayes_mysql.sql * Create the user text/html 2008-02-09T10:46:45-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_virtualmin_setup Introduction Virtualmin is a powerful and flexible hosting control panel that integrates with webmin. We will be using it to provide the virtual hosting functions such as creation of domains, accounts and maintaining configurations on the system. Start services You need to start up services that are required to be able to configure virtualmin. Start the following services text/html 2008-02-05T06:18:11-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_vsftpd_setup Introduction We will use vsftpd as our ftp server. This has a better track record as opposed to the proftpd & wuftpd servers. Basic setting Our basic setup disables anonymous users, and enables local system users to connect to the ftp server anonymous_enable=NO local_enable=YES write_enable=YES local_umask=022 anon_upload_enable=NO anon_mkdir_write_enable=NO dirmessage_enable=YES xferlog_enable=YES connect_from_port_20=YES xferlog_file=/var/log/vsftpd.log xferlog_std_format=YES ftpd_banner… text/html 2008-01-16T05:55:01-04:00 http://www.topdog.za.net/centos_5_virtual_hosting_webalizer_setup No configuration is required virtualmin will take care of all the configs text/html 2007-12-23T04:48:54-04:00 http://www.topdog.za.net/code_snippets text/html 2008-01-23T06:12:26-04:00 http://www.topdog.za.net/configure_clamav Base config This clamav installation with use both the official signatures as well as the sanesecurity signatures that are used combat image and pdf spam as well as phishing attacks. * Add the clamav user to the exim group. # usermod -G exim clamav * Configure clamd to listen to unix socket in the file /etc/clamd.conf text/html 2008-12-18T04:45:18-04:00 http://www.topdog.za.net/configure_exim Introduction To run exim with mailscanner you need 2 configuration files one for the daemon that will listen on port 25 and accept incoming mail and another for the exim process that will deliver the clean mail that has been scanned by mailscanner. You also require 2 queues one for incoming and the other for clean mail that has been scanned. text/html 2008-02-14T04:32:34-04:00 http://www.topdog.za.net/configure_fuzzyocr We will be storing the image hashes in a mysql database to improve on performance such that images that we have already scanned do not get scanned again as OCR is a resource intense activity. Create mysql Database * The sql script creates the database and tables and adds a user fuzzyocr with the password fuzzyocr text/html 2009-07-06T07:26:23-04:00 http://www.topdog.za.net/configure_mailscanner Intro Mailscanner has several configuration options i will only dwell on those that are needed to get the system working. To further customize the system please read the mailscanner documentation or look at the sample configuration files that i have provided. text/html 2010-08-16T09:31:51-04:00 http://www.topdog.za.net/configure_mailwatch More info on the baruwa interface can be found here Patch for enhanced release This patch makes mailwatch to release messages via mailfeeder re-injecting the actual message through the smtp server to make it appear like the original message that was sent as opposed to the default mailwatch release that sends the released mail as an attachment from the postmaster account. text/html 2008-02-14T04:23:02-04:00 http://www.topdog.za.net/configure_mysql * Add this to the configuration file /etc/my.cnf socket=/var/lib/mysql/mysql.sock skip-networking This configures mysql to only communicate via the socket not tcp which is better for security and for performance. * start mysql, this will initialize the default databases. text/html 2008-01-11T07:57:04-04:00 http://www.topdog.za.net/configure_razor * Register your razor system # razor-admin -register text/html 2010-01-05T10:53:11-04:00 http://www.topdog.za.net/configure_spamassassin This configuration will use a mysql database to store the bayes information. So we will create a database and user that will be used to connect to the database. We will also be using extra rules (SARE hosted by Daryl C. W. O'Shea <http://www.dostech.ca/>) so we will configure sa-update to download them automatically. The update script also updates the default spamassassin rules from updates.spamassassin.org as well. text/html 2008-02-05T16:47:26-04:00 http://www.topdog.za.net/create_cacert_postfix_certificate Introduction Cacert is a certification authority that provides free certificates, i guess using them is much better that having your own local CA. Install root certificate We need to download the cacert root certificate and install it on the server text/html 2008-06-16T10:24:33-04:00 http://www.topdog.za.net/dhcp_failover Introduction This tutorial will walk you through setting up DHCP fail over on CENTO 5.1 using the default ISC dhcp server, this can easily be adapted to any other Linux distro out there. You will most likely need Fail over in environments where network down time can not be tolerated. My home is runs a DLNA setup so i need my devices to be able to obtain network parameters at all times. text/html 2009-03-04T05:37:48-04:00 http://www.topdog.za.net/exim_cyrus_horde_mailserver_setup Introduction This how to describes the installation and configuration of a mail system on Centos 5.1 with selinux enabled for enhanced security. This system will be able to service HTTP, HTTPS, SMTP, TLS, SMTP-AUTH, IMAP, POP3 clients and is virtual enabled allowing more that one domain to be served from the system. text/html 2009-06-08T07:35:02-04:00 http://www.topdog.za.net/howtos A list of tutorials that i have written. How to setup a Cisco Lab on Linux (Centos 5.2) This howto describes setting up emulation software to run a Cisco practise Lab on Linux (Centos 5.2) How to setup DHCP Failover on Centos This howto describes setting up DHCP failover and redundant DNS. text/html 2008-10-26T05:44:46-04:00 http://www.topdog.za.net/mailscanner_with_communigate_pro_guide In this tutorial we will be installing and setting up Mailscanner as a mail firewall in front of a Communigate pro cluster. This tutorial has been written for the CENTOS 5.x Linux distro but am sure it can be used of any other Linux based systems with little modification. The system will run with selinux in enforcing mode. The components that we will use include: text/html 2009-11-16T07:51:48-04:00 http://www.topdog.za.net/mw_ideas Okay - we'll use this page to collate ideas and plans for MailWatch 2.0. If you make additions to this list or any comments to existing items, then please prefix with your initials e.g. SMF: Like this - and add yourself to the table below. Initials Name SMF Steve Freegard DD Dhawal Doshy MH Matt Hampton SDT Sven De Troch MG Maxime Gaudreault SE Sujith Emmanuel FC Francois Cid PR Phil Ran… text/html 2010-01-06T02:57:34-04:00 http://www.topdog.za.net/other On Safari Catching the big game in the african wilderness My Bush Safari Road Trip Road Trip Airshows SAAF Museum airshow 2009 Motor rallying * Toyota dealer rally Gauteng 2009 * Toyota dealer rally Gauteng 2008 text/html 2009-10-23T12:03:20-04:00 http://www.topdog.za.net/php_couchdb_extension-0_0_1 This PHP extension wraps the CouchDB RESTful API, allowing you to access CouchDB servers from within your PHP scripts with easy to use functions. The extension does not encode or decode the JSON response's or requests, you need to do that using the PHP json extension (Built in Support for JSON encoding and decoding is in my svn version only at the moment and requires PHP => 5.2.10). This software is still alpha please use with care, you have been warned. text/html 2010-08-11T03:00:13-04:00 http://www.topdog.za.net/php_couchdb_extension The CouchDB extension allows PHP developers to easily manipulate CouchDB documents stored on CouchDB servers using an object-oriented API. The extension implements most of the CouchDB API with the ultimate goal being full support. The server JSON responses are automatically decoded into native PHP objects or arrays. text/html 2010-02-02T11:56:07-04:00 http://www.topdog.za.net/postfix_dkim_milter Introduction DKIM is an authentication framework which stores public-keys in DNS and digitally signs emails on a domain basis. It was created as a result of merging Yahoo's domainkeys and Cisco's Identified Internet mail specification. It is defined in RFC 4871. text/html 2009-06-08T07:42:35-04:00 http://www.topdog.za.net/postfix_dkim_milter_centos5.1 This howto has been superseded by <http://www.topdog.za.net/postfix_dkim_milter> Introduction DKIM is an authentication framework which stores public-keys in DNS and digitally signs emails on a domain basis. It was created as a result of merging Yahoo's domainkeys and Cisco's Identified Internet mail specification. It is defined in RFC 4871. text/html 2009-06-08T07:45:19-04:00 http://www.topdog.za.net/postfix_dkim_milter_centos5.2 This howto has been superseded by <http://www.topdog.za.net/postfix_dkim_milter> Introduction DKIM is an authentication framework which stores public-keys in DNS and digitally signs emails on a domain basis. It was created as a result of merging Yahoo's domainkeys and Cisco's Identified Internet mail specification. It is defined in RFC 4871. text/html 2009-06-08T07:22:03-04:00 http://www.topdog.za.net/postfix_dkim_milter_centos5.3 Introduction DKIM is an authentication framework which stores public-keys in DNS and digitally signs emails on a domain basis. It was created as a result of merging Yahoo's domainkeys and Cisco's Identified Internet mail specification. It is defined in RFC 4871. text/html 2008-03-10T17:54:01-04:00 http://www.topdog.za.net/postfix_domainkeys_milter Introduction Domainkeys is DomainKeys is a method of e-mail authentication. Unlike some other methods, it offers almost end-to-end integrity from a signing to a verifying Mail Transfer Agent (MTA). In most cases the signing MTA acts on behalf of the sender, and the verifying MTA on behalf of the receiver. DomainKeys is specified in Historic RFC 4870, which is obsoleted by Standards Track RFC 4871, DomainKeys Identified Mail (DKIM) Signatures. according to the wikipedia. So why a how to on it wh… text/html 2010-05-14T08:42:07-04:00 http://www.topdog.za.net/projects Baruwa An Ajax enabled mailscanner front-end more info here PHP CouchDB extension The CouchDB extension allows PHP developers to easily manipulate CouchDB documents stored on CouchDB servers using an object-oriented API. The extension implements most of the CouchDB API with the ultimate goal being full support. The server JSON responses are automatically decoded into native PHP objects or arrays. For details and to download go here text/html 2009-01-25T07:58:02-04:00 http://www.topdog.za.net/ps3_media_server Introduction The Sony Play station 3 is a DLNA compatible device, DLNA is a framework where home electronics can share digital media and content seamlessly. This tutorial will provide instructions on setting up your Ubuntu hardy computer to share your video, music and photos, allowing you to play them through your DLNA compatible devices. Although several other open source media servers exist, i chose to use Fuppes due to its built in support for transcoding. text/html 2009-01-25T08:00:02-04:00 http://www.topdog.za.net/ps3_media_server_centos5 Introduction The Sony Play station 3 is a DLNA compatible device, DLNA is a framework where home electronics can share digital media and content seamlessly. This tutorial is a followup to the previous howto on ubuntu. Given that i like most others use CENTOS as their server distribution of choice, i find it fitting to run my DLNA server on it as well. Although several other open source media servers exist, i chose to use Fuppes due to its ease of use as well as built in support for transcoding. text/html 2008-01-29T13:53:41-04:00 http://www.topdog.za.net/setup_network_install_server This howto will describe how to setup Linux network install server. We will be using pxeboot and dhcp to allow for bare metal installation without the need for physical media. Network install servers are essential when large numbers of machines need to be setup or in cases where machines are frequently setup as well as for deployment of xen virtual machines. text/html 2010-01-06T02:43:06-04:00 http://www.topdog.za.net/start Here you will find my tutorials, code snippets, personal stuff as well as system administration tips on *nix. Okay enough with the chit chart go straight to the stuff below. * Projects * Howtos * Code snippets * Tips * Other info Latest distro releases Latest packages * Am a Sysadmin, passionate about Open source software. * I contribute to Fedora Linux, maintaining packages as well as reviewing package submissions. * Wanna get in touch well drop me a mail <topdog@fedorapro… text/html 2010-08-16T09:22:33-04:00 http://www.topdog.za.net/tips Restoring grub This will help you to restore your grub boot loader if it has been overwritten by another operating system say M$ windows. * Boot using a live cd or boot into rescue mode * Type grub * Type root(hd0,0) where the first 0 is the disk and the second is the partition substitute to fit your disk layout * Type setup (hd0) where the 0 is your disk substitute to fit your installation. * Type quit * reboot