UPWORK/ODESK guru: Tips and Tricks for clients

skype: upwork.link , email: [email protected]

Archive for September, 2013

Tayn baseboard: How to flash motherboard BIOS from Linux.

without comments

You’ve finally made the move to a Windows-free computer, you’re enjoying your brand new Linux OS, no trojans/viruses, no slowdown, everything’s perfect. Suddenly, you need to update the BIOS on your motherboard to support some new piece of hardware, but typically the motherboard vendor is offering only DOS based BIOS flash utilities. You panic! Fortunately, this problem is easy to solve …

Step 1: Download FreeDOS boot disk floppy image

Read the rest of this entry »

Written by spectre

September 23rd, 2013 at 9:14 pm

Posted in Tips and Tricks

CentOS: Securing Sendmail with TLS

without comments

One of the most common uses of network systems is for e-mail-basedcommunications. As such, a great deal of attention has been given to securing e-mail systems. Howe
ver, most of this focus has been in two areas – security at the message level, using PGP or S/MIME, and confidentiality in the authentication process for mail retrieval, i.e., using APOP or SSL-based IMAP. This still leaves mail server-to-server traversal vulnerable to several attacks.

The introduction of basic cryptography into a mail server-to-server session alleviates most of these risks. Mail transport agents(MTA) and software such as Sendmail or Postfix can be augmented to handle their communications over transaction layer security(TLS) channels. This provides for a number of services, including confidentiality, integrity protection and strong authentication.

This article will introduce the features and use of SMTP over TLS as defined in RFC 2487, as well as illustrate their setup in the Sendmail package. We will cover cryptography basics, though not delve into the mathematics of cryptosystems and simple mail transfer protocol (SMTP) and extended simple mail transfer protocol(ESMTP) basics.

Some Basics of Cryptography

Read the rest of this entry »

Written by spectre

September 22nd, 2013 at 7:33 pm

Linux Network Admin : SENDMAIL: sendmail’s options

without comments

Опции sendmail

Пакет sendmail имеет ряд параметров, которые позволяют Вам настраивать выполнение ряда задач. Я рассмотрю лишь основные,полный перечень огромен. Чтобы конфигурировать любые из этих параметров, Вы можете определять их в
файле конфигурации m4, что является предпочтительным методом, или вставлять их непосредственно в файл sendmail.cf. Например, если нужно, чтобы sendmail запускал новый процесс для каждого сообщения почты, нужно добавить строку к файлу конфигурации m4:

Read the rest of this entry »

Written by spectre

September 18th, 2013 at 2:52 pm

Posted in sendmail

Where to put the check_* rulesets in sendmail

without comments

check_* in .mc

Usually the

1
sendmail.cf

file should be built from a

1
.mc

file with help of the m4 macro language processor . Use the supplied HACKs or put the rules(e.g.,check_mail or check_rcpt ) as given into the .mc file. Make sure that you have the CODE>LOCAL_CONFIG and

1
LOCAL_RULESETS

in front of the respective sections, otherwise there will be some problems!

Read the rest of this entry »

Written by spectre

September 18th, 2013 at 2:34 pm

Posted in sendmail

Protected: Типовые задачки по sendmail. Часть первая.

without comments

This content is password protected. To view it please enter your password below:

Written by spectre

September 18th, 2013 at 2:26 pm

Posted in sendmail