Traffic diversion in EIGRP / OSPF

Dear All,
I am new to routing protocols.
I need to connect 2 branches with redundant links.
My requirement is to use only one link as a active and second link in standby. Both links having same Bandwidth.
What protocol I should use, ospf or eigrp?
how much time it take for failover ?
if primary link is having some fluctions, what commands i need to use to do failover the traffic if i use ospf or eigrp.
If links having same bandwidth, then load balancing is by default enabled in case of eigrp or ospf?
Please help me out with doing this small setup.

It depends where the failure is. If they are point to point links then if one end fails the other end should go down as well. However if these are being provisoned by a provider they may well appear point to point but they may go through provider switches in which case if one end fails the other might still think it is up.
The only way to test if to shut one end down and see if the other end goes down as well.
Lets assume they do behave like that and you are using HSRP. You are also tracking within HSRP the status of the point to point link -
1) if the link itself fails then both routers should see the WAN interface go down and because you are tracking with HSRP both router failover to the othe HSRP router so it all works
2) if the WAN interface on either router fails the other router's WAN interface should go down and again because of HSRP tracking both routers failover.
3) if either active router at each end of the link fails then again the other router's WAN interface should go down and both routers failover.
but -
4) if the LAN interface on one of the active routers fails then it fails over to the other router. But the active router at the other end does not failover because it's WAN link is still up because it was the LAN interface that failed on the router not the WAN interface.
All of the above as i say depends on whether those links act as true point to point links. If they don't then you definitel can't rely on HSRP with tracking for any failover.
So it depends. And if you wanted to be sure of failing over in all scenarios then you may need additional configuration.
Jon

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Eigrp & Ospf

Eigrp & Ospf command line based on convergence time, jitter, delay variation, end to end delay and throughput using packet tracer

(((With a single network you can connect multiple interfaces.))).
Another query about the "network" command or keyword with these IGP protocols,,,,cisco curriculum CCNP1 V3 {9.3.1 Basic BGP configuration} says:
(((The network command is used with IGPs, such as RIP, to determine the interfaces on which to send and receive updates.
The command also indicates which directly connected networks to advertise))).
Won't it be more accurate if he has done it like this :
The network command is used with IGPs, such as RIP, to determine the networks which interfaces belong to
Any correction and comment, thanks

Cisco 2620 eigrp/ospf issues

Greetings,
I'm having issues getting a Cisco 2620 and a Dell Powerconnect 6024 to redistribute via eigrp/ospf correctly which are both at a remote location. I have attached a basic diagram to better show the topology. We have been unable to access the remote site from our main site (which is using a cisco 3600) without a static route for each subnet at the remote site. Hopefully this makes sense.
Cisco 2620 Config:
Building configuration...
Current configuration:
ip subnet-zero
lane client flush
cns event-service server
interface FastEthernet0/0
ip address 10.100.187.1 255.255.255.0
duplex auto
speed auto
interface Serial0/0
ip address 10.100.181.10 255.255.255.252
no ip mroute-cache
no fair-queue
router eigrp 100
redistribute connected
redistribute ospf 1
network 10.0.0.0
no auto-summary
router ospf 1
redistribute connected
redistribute eigrp 100 subnets
network 10.100.0.0 0.0.255.255 area 0.0.0.0
ip classless
ip route 0.0.0.0 0.0.0.0 10.100.181.9
no ip http server
banner motd ^CCC

Timothy
There are a couple of things that I am not clear about concerning your situation. Your diagram shows a single subnet between the Cisco and the Dell. Is everything in the Dell in that single subnet? If so I am not sure why you are running OSPF, since there will not be any OSPF routes to redistribute.
If the diagram is incomplete and there are routes in OSPF that need to redistribute to EIGRP then there is an issue in the configuration. There is no default metric configured under router EIGRP. Without a default metric routes from another protocol (OSPF) will not redistribute into EIGRP.
I think it is also an interesting question whether the 2620 and the 3600 routers are forming EIGRP neighbor relationships. Failure to form EIGRP neighbor relationships could also cause the symptoms that you describe.
HTH
Rick

Can BGP be used like EIGRP / OSPF?

Can BGP be used like EIGRP / OSPF? Can some one explain?

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
As Peter described, normally you wouldn't use BGP in place of an IGP like EIGRP or OSPF.
However, if you're a masochist, you could.
For example, if all your routers were connected by p2p links, you could configure each router in its own AS and run them as eBGP peers.
What Peter was alluding to, normally interior BGP peers run as iBGP peers, but then each requires a connection to every other peer (full mesh). (There's also BGP route reflectors or BGP confederations, which limit the need for interior iBGP peering to all other iBGP routers, but neither deals with how the iBGP routers "know" how to route to their required peers.) Normally an IGP protocol is used to provide reachability, but you could do the same with static routes. Of course, whether you have an IGP or use static routes that maps out the whole interior topology they both beg the question of why also then have iBGP too (if being used just for the interior topology).
There's a limit to the number of AS numbers, especially if using just the private range, so you could combine the two approaches, such as having small clusters of iBGP peers (maybe 2 or 3) which eBGP peer to other clusters.
If you did go to all the trouble, you would then find that BGP will likley converge slower than most IGPs and unless you do some manual policy configuration, BGP won't path select much better than RIP.
What BGP does well is handle massive route tables (like the Internet) and allow very sophiscated (manual) routing policies. However, both are usually not as desirable for an IGP.

Conversion EIGRP- OSPF in production environment

Imagine I have a production network running EIGRP, total of 5 routers. (2 routers in the data center, 1 router each branch office). I would like to setup the main office as "Area 0" and the respective branch offices I would setup as "Area subnet#_branch_office". I am wondering whether setting up Stub areas in the branch offices could be a good approach.
What would be the best way to approach a migration to OSPF ? Do you start with redistribution from EIGRP to OSPF, or would you just re-advertise networks running EIGRP with OSPF ? I would appreciate directions on this.

Marlon,
Migrating from EIGRP to OSPF should be an easy process. You can configure OSPF concurrently while EIGRP is running and that wouldn't impact routing as EIGRP routes are preferred over OSPF because it has a lower (better) admin distance than OSPF. Once you are done fully configuring OSPF then you can start removing EIGRP. At this point, the EIGRP route will be lost and OSPF route should replace it in the routing table. The only exception to this is if you have external EIGRP route then the OSPF route might take its place and can create problems. But, there are ways even this problem can be addressed.
As far as your question about stub routing is concerned, it's not a bad idea to configure as a stub if the network is a hub-and-spoke. Infact, you can go level further and configure them as totally-stub routers and that way the branches will only learn a default route from the hub device.
HTH
Sundar

Voice Traffic over MPLS-enabled OSPF running backbone links

Hi All;
We have running frame-mode MPLS backbone and OPSF as well. Voice as real-time traffic is passing through our backbone links and marked with precedence 5 as an ordinary behaviour.
What i face is that i can not balance the voice traffic between the uplinks of the LER routers through LSR routers. Let me summarise like this.
I have a PE that has 4xE1 connection as uplinks terminated at two different LSRs. However, when i look at the voice traffic distribution from PE to Ps,the general attribute is voice traffic is choosing only one E1 and uses it. And other links are not used so much by voice traffic. And this causes poor quality of voice because, it exceeds the amount of the reserved bandtwidth that is defined via LLQ under the backbone links. I have also re-defined the priorty class bantwidth and raised it as much as it can be defined, but now, the business in contract traffic is under danger. :)
As OSPF does not support unequal load-balancing and also "load-sharing per-packet" command sucks the voice traffic, there is nothing to balance the voice traffic on the backbone links.
By the way, i have defined MPLS/TE tunnels that are PE-PE tunnels, according to my observations of voice traffic goes to where. I tried to balance the output traffic somehow but the situation is still the same. Sometimes, traffic chooses one tunnel and goes over there. In fact this problem bears with CEF itself but this is another case.
So any suggestion how i can come over this obstacle. Thanks in advance.
Regards,
Baris.

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
BTW, 20 Mbps can push the practical performance capacity of a 2821.
class-map match-any LLQ
!match your VoIP bearer traffic here
policy-map Shape20M
class class-default
shape average 17000000 !we're shaping 15% slower to allow for L2 overhead
service-policy Sample
policy-map Sample
class LLQ
priority percent 30
class class-default
bandwidth remaining percent 100
fair-queue
interface tunnel #
ip tcp adjust-mss 1436
ip mtu 1476
service-policy output Shape20M
tunnel path-mtu-discovery
keepalive 1

Advertise route as OSPF, but I see it as "EIGRP" ?

Sorry if this is a stupid question but I don't understand well why I am able to see route
D 152.1.1.4/30 on RouterD.
Basically the network 152.1.1.4/30 has been advertised via OSPF on RouterC interface. However, that was not advertised there as an EIGRP route...
How come I am able to see it on RouterD as EIGRP ?
Please find attached complete run config.
Please note I am doing one-way redistribution EIGRP->OSPF. Therefore in my view that doesn't justify the EIGRP route for 152.1.1.4/30 on RouterD.
RouterB so]===[s0 RouterC s01]===[s0 RouterD]
RouterB s0=152.1.1.5/30
RouterB S1=152.1.1.6/30
RouterD S0=152.1.2.2/24
From RouterD:
Gateway of last resort is not set
152.1.0.0/16 is variably subnetted, 3 subnets, 2 masks
C 152.1.3.0/24 is directly connected, Loopback0
C 152.1.2.0/24 is directly connected, Serial0/0
D 152.1.1.4/30 [90/2681856] via 152.1.2.1, 00:01:58, Serial0/0

Just one correction here.
network 152.1.1.5 0.0.0.0 area 0 is CORRECT, if the interface IP is 152.1.1.5.
The main misunderstanding encountered is: the network statement and especially the wildcard mask determine the routing updates sent. Wrong.
The only purpose the network statement serves in OSPF is to identify the IP interfaces where to send hellos and include the networks with configured mask into routing updates (LSAs).
So f.e.
router ospf 10
network 0.0.0.0 0.0.0.0 area 0
has nothing to do with a default route. it just means: "Include any active IP interface into OSPF and send hellos." Still configured network/mask would be announced correctly.
Writing this I would even recommend instead of 0.0.0.0 0.0.0.0 to use
network 152.1.1.1 0.0.0.0 area 0
because you will not unintentionally enable OSPF on an interface, where it should not start (f.e. towards ISP).
Hope this helps! Please rate all posts.
Regards, Martin

ASA Transparent mode multicast traffic in 8.2 and 8.4

Hi,
When i configure 8.2 in trasparent mode and deploy the a network that was wrok on EIGRP after that i found the neighborship was stop when i allow the mutlicast address and prtocol on outside interface it was start the working But when i deploy an ASA with 8.4 IOS and then allow the multicast address and protocol both the interface (Inside and outside) after that it was start working.
So i want to know that what the reasion to allow multicast address and protocol on 8.4 IOS for both interface. I am not able to find any answer for this.

Hi Mahesh,
By default ASA in transparent mode do not allow any packets not having a valid EtherType greater than or equal to 0x600. As per my knowledge this concept remain same for all versions of ASA. Most control plane protocols are denied.
ASA in transparent mode only allows ARP, broadcast traffic, TCP and UDP inspected unicast traffic.
For EIGRP to work through transparent firewall, we need to open ACLs in both direction for multicast and unicast both type of EIGRP traffic on all versions of ASA Firewall.

Nexus 7010 OSPF Equal Cost Paths

Hello,
I currently have two physical links connecting one data center to another. These are both 10Gb links and I have manually set the cost to the primary link to '1' and the secondary link to '10'. My question is, if I set the secondary link to '1' they would have equal cost routes. What is the selection process at this point? Will equal cost load balancing automatically kick in and use both links?
Thank you,
Scott

Scott
Haven't used Nexus switches but generally yes it should do depending on the routing protocol ie. statics, EIGRP, OSPF etc. will use equal cost paths if they are in the routing table.
BGP is different in that without further configuration it picks just one path so there is only one entry in the routing table.
By default it will use per destination load sharing and the default on Nexus is destination IP address and port number to choose which link to use.
"sh ip load-sharing"
will show you the current method it is using.
Jon

3750x IP Services EIGRP?

The switch doesn't take the "no auto-summary" command for EIGRP. Running C3750E-UNIVERSALK9-M IPServices feature on a 3750x-12. Am hoping to use as a layer 3 switch but it has to fully run EIGRP, do I have the wrong IOS or the wrong switch?

If you have IP Services license, it means you can run full EIGRP, OSPF, BGP, etc..
As for not being able to apply the "no auto-summary" command, it maybe because in the newer IOS version it is by default disabled.
from the command reference guide:
Command Default
The behavior of this command is enabled by default (the software does not send subprefix routing information across classful network boundaries).
Cisco IOS Release 15.0(1)M, 12.2(33)SRE, 12.2(33)XNE, Cisco IOS XE Release 2.5, Cisco IOS Release 12.2(33)SXI4 and Later Releases
The behavior of this command is disabled by default (the software sends subprefix routing information across classful network boundaries).
link:
http://www.cisco.com/c/en/us/td/docs/ios/iproute_eigrp/command/reference/ire_book/ire_a1.html#wp1062919
HTH

C3640 stops processing traffic over ethernet

Hi
I have a C3640 with a NM-2FE2W-V2, neighboring with a C2621 over Fa0/1. They both speak OSPF with each other.
Problem: Within a period of 1-2 hours, the Fa0/1 stops receiving, or, let's say, processing incoming traffic.
The strange thing is, the problem does not occur if I connect a simple PC to the Fa0/1; it will continue to work uninterruptedly.
Additional info: The two routers have fixed settings 100/full. Until the problem occurs, traffic is being processed normally by the C3640. Using a sniffer, I could prove that during problem occurence, traffic (e.g. OSPF, CDP, ICMP...) still gets to the Fa0/1. It just simply does not increase the incoming packet counter anymore. Though the int will stay in up/up mode. Only a shut/no shut solves the problem, unplugging/plugging the ethernet cable doesn't.
Running IOS 12.2(28a).
Does anyone have an idea? Thanks for any help.
Toni

Hi m.lammerse
I wish to believe a software upgrade would help. After all, I upgraded this router to the second last available GD release to being able to support the NM module. The router is in a productive environment and I have to keep downtime as low as possible.
See the sh int fa0/1 output below. Notice that it is exactly one week ago, when I cleared the counters. At that time, the problem was already present. You'll notice, that the interface still continues to send traffic.
I was not able to spot any sign in the buffered log which could have helped me to figure out the reason.
chreh-router1#sh int fa0/1
FastEthernet0/1 is up, line protocol is up
Hardware is AmdFE, address is 0009.7c9b.5b02 (bia 0009.7c9b.5b02)
Description: darkfiber to chgra-router1
Internet address is 192.168.20.9/30
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, 100BaseTX/FX
ARP type: ARPA, ARP Timeout 04:00:00
Last input 1w0d, output 00:00:00, output hang never
Last clearing of "show interface" counters 1w0d
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog
0 input packets with dribble condition detected
135580 packets output, 12700782 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
chreh-router1#

Dynamic routing alternative between ASA and edge routers?

This is the current setup between two edge routers and an ASA 5580. The edge routers carry approximately 9200 BGP routes with ISP A also supplying the default route. Is there a good, i.e. has been successfully implemented, dynamic routing situation between the edge routers and ASA such that the ASA can send traffic to the particular edge router that carries the best specific route?

Hello,
Let's remember that the ASA was built as a High-Level Next Generation Firewall.
That does not mean it's not useful for routing but here we are talking about thousands of routes, I do not think there will be a performance issue on the FW because of that. I mean you have one of the greatest Cisco Firewalls (functionality and power speaking).
So if that's the case and you really want to do that you will need to implement either RIP,EIGRP,OSPF on the link and then do the redistribution on the routers.
Makes sense?
Regards,
Jcarvaja
CCIE 42930

ACE RHI problem

Hello,
I have two 6509 switches with ACE modules installed and configured as active/standby. There is no FWSM installed, so MSFC shares a common subnet with the external interface of ACE. On both MSFCs, I can see the static route injected (RHI) by ACE. However, those routes are different. On the MSFC hosting the active ACE, the next hop of the static route installed is the alias IP address of the external ACE interface. On the MSFC hosting the standby ACE has the next hop as the IP address of the external interface of the standby ACE not the alias.
This causes a problem when traffic is routed through the second MSFC where it will send traffic destined to my VIP to the standby ACE causing traffic to be dropped.
Why this behaviour happens? I started to see this behaviour after a sudden reboot on the standby ACE. Before that, I am not sure what was the route injected into the second MSFC but I had no problem with my VIP.
Can anyone help me how I can tell the second MSFC to route traffic towards the alias instead of the interface IP?
Thanks.

The TAC case is resolved. Posting back to the community so the solution can be shared with a wider audience.
Thanks to Mohammed for keeping outputs of troubleshooting at the time of problem, it was found that after the standby ACE rebooted, BOTH the active ACE and standby ACE were injecting the host route to the VIP, this is not expected behaviour. The expected behaviour is for the active ACE to inject the host route with the ACE alias IP as the next hop, and the standby to not inject the route.
This problem is due to a software defect CSCsx67908 "When you configure ACEs for redundancy and Route Health Injection (RHI) and the standby ACE reboots, duplicate RHI entries can exist on the supervisor."
ref: http://www.cisco.com/en/US/partner/docs/interfaces_modules/services_modules/ace/v3.00_A2/release/note/racea2_x.html
Software fix integrated is available. There is also workaround by a "FT switchover" on the ACE.
Another workaround by routing is to disable RHI for the VIP, and instead advertise the VIP subnet by routing protocol on the switch supervisor (eg, advertising the connected Vlan via EIGRP, OSPF, etc...).
RHI of the VIP is not enable by default, and can be disabled with the following from ACE:
policy-map multi-match XYZ
class ABC
no loadbalance vip advertise active
More info on RHI can be found here:
http://www.cisco.com/en/US/docs/interfaces_modules/services_modules/ace/vA4_1_0/configuration/getting/started/guide/rhi.html
Regards,
Simon

Implemting a Sprint MPLS/VPN

Hello
I'm implmenting a Sprint MPLS/VPN network. This is a point to point between two of my locations. The connection is handed of to me as a serial connection and I will be connecting to cisco 2800 on bothe ends. Does anyone have what a sample config might look like for my Cisco rotuer?
Thanks in advance

HI, [Pls Rate if HELPS]
In addition to JOE POST,
You need to configure as normal CE Router. You can handover your Network Traffic either via some DYNAMIC Routing Protocols (BGP, EIGRP, OSPF, RIP) or Static Routing at LAST MILE towards your Service Provider.
At the Service Provider Side, the Connected Interface with your CE will be added with "ip vrf forwarding " command. Where seperate Routing instance will be maintained on top of Global Routing Table. The MPLS Labels are swapped over their Backbone / partner - NNI to carry your traffic over a Label Switched Path.
For an MPLS to work, the IP-CEF will be enabled. This kind of MPLS Technology, will enable fast processing of Packets and Traffic over the Large Scale Network.
Similarly the RT & RD Values are used to distinguish the Customer Prefixes. The RT export and Import will be done at end - to - end at Service Provider Side Routers to make the HO & BO to communicate.
The CE Router will not involve any MPLS / VRF Configuration Technology.
Hope I am Informative.
Pls Rate if HELPS
Best Regards,
Guru Prasad R

WAAS placement

Dear All,
I have to deploy WAAS for one of my client and wanted to know the effect of DMVPN in this scenario.
We have a star topology and we have EIGRP, OSPF and DMVPN implemented. All I wanted to know is that where should the wccp redirection be used. In common scenarios we use wccp 62 ( inbound) on WAN and wccp 61 ( inbound) on LAN. But here the case is little different.
Also we have, 4507 LAN core switch and 3845 as a core routerwith no redundancy. where should the interception be configured in the DMVPN scenario?
Thanks

Thanks DAN for the reply. The topology is as follows
one core router 3845 acting as a hub ( Central /Data Centre)
all branch routers connecting to the HUB( Data Centre 3845) through service provider default route.
one router at each branch.
L3 VPNs provided by SPs and the branch router uses default route.
In Addition to this DMVPN are implemented in this scenario.
Note that this is a perfect STAR topology.
Now I was asking that where should i apply the wccp redicrection. As in normal scenario we apply this on LAN and WAN interface as follows
int WAN
ip wccp 62 in
int LAN
ip wccp 61 in
But in the case of DMVPN will this work ? or the encrypted traffic on WAN interface will cause problem. I am applying redirection on router and it is possible that the WAE is directly connected to the router interface or to the switch ( VLAN scenario)
I hope I am clear now

Traffic diversion in EIGRP / OSPF

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