I am currently working as a Senior Field Consultant. I started my professional career in 1999 in India. In the year 1999 I decided to transition from the Retail Industry to hard core Information Technology, which was always my strength and desire. I realised my strengths and keen interest when I worked on Dbase III Plus a few years back but due to various constraints I could not pursue my career at that point in time. I have worked in various capacities in the fields of Software Technology, as Systems administrator, Systems Support Engineer, Implementations Engineer and Senior Implementation Engineer. Currently, I am based as Senior Field Consultant for a Microsoft Gold Partner in Oxford, U.K.
I am certified in various disciplines
CCIE # 23368
CCNP
CCNA
CCA
MCSE NT, 2k & 2k3
MCSA 2k & 2k3
MCSE 2k & 2k3 (Messaging & Security)
MCSA 2k & 2k3 (Messaging & Security)
I devote my free time to the technology communities. I believe knowledge grows by sharing and I love to share my knowledge. I believe it is important to be passionate and really enjoy whatever you do. I am also the founder and maintain Ahmedgroup (http://www.ahmedgroup.co.uk)
In part 2 of the HSRP series I will cover the configuration & show you how to verify the configuration.
I have put together a Microsoft® Visio® diagram which shows you a lot more than simply Hot Standby Router Protocol (HSRP). You need to concentrate on Hot Standby Router Protocol (HSRP)
configuration alone and at a very high level look at the diagram and think about "High availability".
The key to this lab would be to ensure without any administrative overhead i.e. changing of default gateways on any device including the desktops, configuration of new routers etc...achieve end to end connectivity!!!
I shall not cover all of the topics in depth and focus primarily only on Hot Standby Router Protocol (HSRP) but I will touch on the other things slightly and try to cover different bits in the future articles on the similar diagram.
But the key is to keep in mind is "High availability".
1. All 3 LANS have two paths to reach the Head Office & vice versa.
2. Equal cost load balancing can be achieved in this scenario by using various protocols. Note: for an example please refer to the ISP rotuer config attached below at the end of this article.
3. Resilience for your LAN users using Hot Standby Router Protocol (HSRP) on each site to access resources located at the Head Office.
4. If something goes wrong at a specific POP at the service provider (SP) OR the router on that link the alternate Serial link can be utilized from a different service provider (SP) at an entirely different POP to reach the Head Office.
5. If both Serial Links between each site is not an affordable solution to be utilized simultaneously the (second serial link can be on contract on a per (MB) utilization contract) than you can manipulate the metric in such a way that only (1 serial link) is utilized at any given time and the second path is injected into the routing table only when the primary route is not available and the secondary link will be used purely for redundancy.
6. "High availability" can be also considered at places like HO for the switches which plug-in to the servers to ensure if one of the switches fail the servers can use there fail-over connection network interface card (NIC 2) to secondary switch & still provide a successful connection to all user sessions.
The above might seem a lot of information & confusing for a few reading this article but because we are actually implementing Hot Standby Router Protocol (HSRP) for the primary purpose to ensure "High availability" is achieved for users on the LAN at each remote office & HO users, so they can access "resources" at Head Office 24 * 7.
I did not want to simply give a basic diagram of two routers / switches and complete this article, the idea was to give you an enterprise diagram and give you the feel of what can be achieved and the benefits in a multi site environment.
Finally it is time for some hands on J
Now lets start the configuration what we have all been waiting for: :)
1. Enable HSRP group & virtual ip add:
R1(config-if)#standby ?
<0-255> group number
authentication Authentication
delay HSRP initialisation delay
ip Enable HSRP and set the virtual IP address
mac-address Virtual MAC address
name Redundancy name string
preempt Overthrow lower priority Active routers
priority Priority level
redirect Configure sending of ICMP Redirect messages with an HSRP virtual IP address as the gateway IP address
timers Hello and hold timers
track Priority tracking
use-bia HSRP uses interface's burned in address
version HSRP version
R1(config-if)#standby 12 ?
authentication Authentication
ip Enable HSRP and set the virtual IP address
mac-address Virtual MAC address
name Redundancy name string
preempt Overthrow lower priority Active routers
priority Priority level
timers Hello and hold timers
track Priority tracking
R1(config-if)#standby 12 ip 10.10.10.100
2. Define the HSRP Priority:
R1(config-if)#standby 12 priority 150
Note: As discussed in Part 1 the default priority is (100)
3. Enable Preempt.
R1(config-if)#standby 12 preempt
4. Define HSRP group name.
Default: HSRP has a way to define the name by default. Example: [ IP redundancy name is "hsrp-Et0/0-12" (default) ] Et0/0 = the interface we are activating Hot Standby Router Protocol (HSRP).
R1(config-if)#standby 12 name ?
WORD name string
R1(config-if)#standby 12 name HO-LAN-DG
5. Enable Tracking & the decrement value for the tracked interface.
R1(config-if)#standby 12 ?
authentication Authentication
ip Enable HSRP and set the virtual IP address
mac-address Virtual MAC address
name Redundancy name string
preempt Overthrow lower priority Active routers
priority Priority level
timers Hello and hold timers
track Priority tracking
R1(config-if)#standby 12 track ?
<1-500> Tracked object number
Async Async interface
BVI Bridge-Group Virtual Interface
CDMA-Ix CDMA Ix interface
CTunnel CTunnel interface
Dialer Dialer interface
Ethernet IEEE 802.3
Lex Lex interface
Loopback Loopback interface
MFR Multilink Frame Relay bundle interface
Multilink Multilink-group interface
Port-channel Ethernet Channel of interfaces
Serial Serial
Tunnel Tunnel interface
Vif PGM Multicast Host interface
Virtual-PPP Virtual PPP interface
Virtual-TokenRing Virtual TokenRing
R1(config-if)#standby 12 track serial ?
<0-6> Serial interface number
R1(config-if)#standby 12 track serial 1/0 ?
<1-255> Decrement value
<cr>
R1(config-if)#standby 12 track serial 1/0 60
6. Verify the configuration.
R1(config-if)#do sh run int e 0/0
Building configuration...
Current configuration : 210 bytes
!
interface Ethernet0/0
ip address 10.10.10.1 255.255.255.0
full-duplex
standby 12 ip 10.10.10.100
standby 12 priority 150
standby 12 preempt
standby 12 name HO-LAN-DG
standby 12 track Serial1/0 60
end
R1#sh standby
Ethernet0/0 - Group 12
State is Active
2 state changes, last state change 00:01:28
Virtual IP address is 10.10.10.100
Active virtual MAC address is 0000.0c07.ac0c
Local virtual MAC address is 0000.0c07.ac0c (v1 default)
Hello time 3 sec, hold time 10 sec
Next hello sent in 1.612 secs
Preemption enabled
Active router is local
Standby router is 10.10.10.2, priority 100 (expires in 7.140 sec)
Priority 150 (configured 150)
Track interface Serial1/0 state Up decrement 60
IP redundancy name is "HO-LAN-DG" (cfgd)
R2#sh run int e 0/0
Building configuration...
Current configuration : 185 bytes
!
interface Ethernet0/0
ip address 10.10.10.2 255.255.255.0
full-duplex
standby 12 ip 10.10.10.100
standby 12 preempt
standby 12 name HO-LAN-DG
standby 12 track Serial1/0 50
end
R2#sh standby
Ethernet0/0 - Group 12
State is Standby
1 state change, last state change 00:03:10
Virtual IP address is 10.10.10.100
Active virtual MAC address is 0000.0c07.ac0c
Local virtual MAC address is 0000.0c07.ac0c (v1 default)
Hello time 3 sec, hold time 10 sec
Next hello sent in 1.624 secs
Preemption enabled
Active router is 10.10.10.1, priority 150 (expires in 7.060 sec)
Standby router is local
Priority 100 (default 100)
Track interface Serial1/0 state Up decrement 50
IP redundancy name is "HO-LAN-DG" (cfgd)
Debugging HSRP
debug standby
debug standby errors
debug standby events
debug standby events terse
debug standby events track
debug standby packets
That is all you need to get your HSRP configured a few commands and you are in business.
You can simply now configure your entire Head office to point to [ 10.10.10.100 ] as there default gateway.
For other HSRP config for R3 / R4 / R5 / R6 you will find them in the config files attached at the end of this article.
Now you can simulate this entire lab on your desktop using dynagen. You will find at the end of this article all the files including the show outputs and the dynagen file for running this lab successfully.
Good Luck :)