Tips & Tricks: Disable Prompt "more" on Cisco

If we execute or run a command (eg: show running or show interfaces) on cisco console, we'll see a prompt "--more--" at the bottom if the output command exceed the length of the screen.  You can disable it by configuring terminal length like this:

1:  line con 0  
2:   length 0  
3:  line vty 0 4  
4:   length 0  

BGP Confederation

BGP confederation divide an AS into sub AS running eBGP on every router, or we can say that it is a group of router running eBGP, but known as a single AS from outside. BGP confederation can reduce the iBGP mesh inside an AS, besides BGP route reflector. BGP confederation is more complex than route reflector, since we have to configure for every router inside a confederation. 

Here is our topology. We use 4 router running BGP, consist of 3 router within a confederation and 1 router from outside. Router R4 will recognize ASN R3 as 100, not 65003. To activate BGP confederation on cisco router, use the following command:

1:  bgp confederation identifier <asn>   
2:  bgp confederation peers <sub-asn 1> <sub-asn 2> <sub-asn ...>  

bgp confederation identifier refer to confederation's ASN, in this topology, our confederation's ASN is 100. And bgp confederation peers refer to sub ASN for all peers router.

BGP Route Reflector

BGP has a loop prevention mechanism to prevent routing loop in the network, but there is different implementation this mechanism in eBGP and iBGP. eBGP using AS path attribute to do loop prevention. while iBGP using split horizon mechanism(in iBGP, all of routers will use the same AS, so it can't use AS path to prevent routing). By using split horizon mechanism, a route received from iBGP neighbor won't be advertised to any other iBGP neighbor. So we need a full-mesh network in iBGP.

Writing or not writing

Someone has told me why make a writing on your blog. Does anyone read that? Well, i don't care whether  anyone will read my writing or not, i just care about my writing skill :). So let's begin writing.

Simple OSPFv3 on Cisco Router

OSPFv3 is designed to use in IPv6 protocol. It has the same fundamental mechanisme just like OSPFv2 on IPv4. In this article, we will configure simple OSPFv3 using 2 cisco router.  Note that, before we enable OSPFv3 on cisco router, we need  to enable IPv6 unicast-routing and  enable IPv6 on the interface.  

Here is the configs of our router:

Instalasi Xen di Debian

Xen merupakan salah satu teknologi virtualisasi berbasis opensource, yang memungkinkan beberapa sistem operasi berjalan dalam hardware komputer yang sama secara konkuren.

Instalasi Xen

Install paket-paket Xen dari repositori:
root@local# apt-get install xen-tools xen-linux-system-2.6.32-5-xen-686 xen-utils-4.0 xenstore-utils xen-hypervisor-4.0-i386

Setup DKIM (DomainKeys Identified Mail)

DKIM (DomainKeys Identified Mail) adalah salah satu metode untuk email authentifikasi yang mengijinkan penerima email untuk melakukan verifikasi bahwa pesan/email yang di terima datang dari domain dan server yang benar dengan melakukan pengecekan alamat email pengirim dan isi pesan secara terintegritas. DKIM dikembangkan berdasarkan teknik DomainKeys milik Yahoo. DKIM akan sangat berguna jika traffic outgoing email banyak yang menuju ke layanan email Yahoo atau Gmail, tanpa DKIM, mungkin saja email yang kita kirim akan dikategorikan sebagai junk mail atau spam oleh mereka.