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GNOME Terminal – running process/command name in tab title

How can I put the current running process name into a GNOME Terminal tab title (or title bar when there’s only one tab)? To clarify, I want the tab title to update when I run a process.

This works perfectly for me with Gnome-Terminal/Terminator:

# If this is an xterm set the title to user@host:dir
case "$TERM" in
xterm*|rxvt*)
    PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD}\007"'
 
    # Show the currently running command in the terminal title:
    # http://www.davidpashley.com/articles/xterm-titles-with-bash.html
    show_command_in_title_bar()
    {
        case "$BASH_COMMAND" in
            *\033]0*)
            # The command is trying to set the title bar as well;
            # this is most likely the execution of $PROMPT_COMMAND.
            # In any case nested escapes confuse the terminal, so don't
            # output them.
                ;;
            *)
             echo -ne "\033]0;${USER}@${HOSTNAME}: ${BASH_COMMAND}\007"
                ;;
        esac
    }
    trap show_command_in_title_bar DEBUG
    ;;
*)
    ;;
esac

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Seriously, what is Big Data?

Big Data Defined

The easiest answer: Big Data is your data, structured and unstructured.

There’s nothing new about the notion of big data, which has been around since at least 2001. It’s the information owned by your company, obtained and processed through new techniques to produce value in the best way possible. Big data may be as important to business – and society – as the Internet has become. Why? More data may lead to more accurate analyses.

Ask any Big Data expert to define the subject and they’ll quite likely start talking about “The three V‘s”. As far back as 2001, industry analyst Doug Laney (currently with Gartner) articulated the now mainstream definition of big data as below:

Volume. Many factors contribute to the increase in data volume. Transaction-based data stored through the years. Unstructured data streaming in from social media. Increasing amounts of sensor and machine-to-machine data being collected. In the past, excessive data volume was a storage issue. But with decreasing storage costs, other issues emerge, including how to determine relevance within large data volumes and how to use analytics to create value from relevant data.
Velocity. Data is streaming in at unprecedented speed and must be dealt with in a timely manner. RFID tags, sensors and smart metering are driving the need to deal with torrents of data in near-real time. Reacting quickly enough to deal with data velocity is a challenge for most organizations.
Variety. Data today comes in all types of formats. Structured, numeric data in traditional databases. Information created from line-of-business applications. Unstructured text documents, email, video, audio, stock ticker data and financial transactions. Managing, merging and governing different varieties of data is something many organizations still grapple with.

Continue reading “Seriously, what is Big Data?”

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Cisco 6500 VSS Configuration

It’s an old draft from 2010. Recently I was designing a network which VSS was on the topics, so it reminded me of the draft.

The Cisco Catalyst 6500 Series Virtual Switching System (VSS) allows the clustering of two chassis together into a single, logical entity. This technology allows for enhancements in all areas of network design, including high availability, scalability, management, and maintenance.

The Virtual Switching System is created by converting two standalone Catalyst 6500 systems to a Virtual Switching System. The conversion is a one-time process that requires a few simple configuration steps and a system reload. Once the individual chassis reload, they are converted into the Virtual Switching System.

All control plane functions are centrally managed by the active supervisor engine of the active virtual switch chassis, including:

Management(Simple Network Management Protocol [SNMP], Telnet, Secure Shell [SSH] Protocol, etc.)
Layer 2 Protocols (bridge protocol data units [BPDUs], protocol data units [PDUs], Link Aggregation Control
Protocol [LACP], etc.)
Layer 3Protocols (routing protocols, etc.)
Software data path

The requirements to convert the 6500 into a Virtual Switching System are:

The VSS requires Supervisor Engine 720 with 10-GigabitEthernet ports. You must use either two VS-S720-10G-3C or two VS-S720-10G-3CXL supervisor engine modules.
The VSS requires 67xx seriesswitching modules.
The VSLEtherChannel supports only 10-Gigabit Ethernet ports.

Continue reading “Cisco 6500 VSS Configuration”

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Network Design rule!

You should always start with “what services do I want to offer”, continue with “how would I best implement them with the simplest possible design”, go down the path of “which functions do I need to make this design work” and finally “which boxes from which vendors fit my needs?”

Ivan Pepelnjak

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IPv6 Subnetting – Overview and Case Study

I’m gonna share an article which I found from Cisco Support Community. Although it’s not that much new, but it’s kinda interesting overview.

The sheer number of bits in an IPv6 address can make IPv6 subnetting intimidating at best. With the addition of a new addressing scheme it’s easy to get lost trying to break up your brand new /48 address across your enterprise.

The New Boss, Same as the Old Boss

Subnetting with IPv6 is not drastically different than subnetting with IPv4, we just need to keep a few things in mind:

1.) Each character in an IPv6 address represents 4 bits (a nibble).
Since 0xF is 1111 in binary, it’s easy to fall back into an IPv4 habit and forget that 0x11 is actually 0001 0001 in binary.

2.) Each IPv6 set represent 16 bits (4 characters at 4 bits each).
Keeping this in mind can make breaking up subnets a bit easier.

3.) Once it’s in binary nothing changes!
It’s easy to get lost in so many binary digits but the math is all the same. Each subnet bit is one fewer host bit and vice versa.

Setting the Ground Rules

The leading practice is to receive at least a /48 prefix from an ISP. This leaves you with 2^80 bits to manipulate (128 bit address – 48 bits that can’t be changed = 80 bits to use). More bits than the entire IPv4 address space! Continue reading “IPv6 Subnetting – Overview and Case Study”

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