6 votes
Accepted

HSRP change priority didn't failover

You forgot to use the standby 5 preempt command. It is also a good idea to set a preempt delay. Hot Standby Router Protocol (HSRP): Frequently Asked Questions: Q. Which HSRP router requires that I ...
Ron Maupin's user avatar
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5 votes
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EIGRP failover - how do i verify it happened?

There is a command made for such checking. Use: show ip eigrp events
Viktor Borisov's user avatar
5 votes
Accepted

Multhoming including incoming connections?

You're mixing up terminology a bit here. There's no such thing as an IPv4 ASN or IPv6 ASN. There's IP space, which is either IPv4 or IPv6, and there are ASN's. An ASN can announce IPv4 prefixes, IPv6 ...
Teun Vink's user avatar
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4 votes
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ASA5550 manual failover question

How do i check the status of failover to make failover is correctly configure. These commands will give a good indicator of the status and configuration show failover show failover state show ...
TDurden's user avatar
  • 1,241
4 votes

EIGRP failover - how do i verify it happened?

Yes, you can confirm that. Once hold-time expires, the former feasible successor route immediately becomes the successor route and is installed in routing table. I do not think we have a log message ...
Hung Tran's user avatar
  • 3,754
3 votes

Cisco 3825 Router - Dual WAN Failover?

HSRP is for your LAN, not your WAN. Normally it is very simple if you use static default routes. On your WAN, you probably have a default route: ip route 0.0.0.0 0.0.0.0 <next hop> A static ...
Ron Maupin's user avatar
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3 votes
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ASA Redendent Failover and stateful link issue

"Everything working good but when i remove g0/6 cable..." --> Does this mean failover is working for you when g0/6 cable is plugged? Please plug back the cable and run the commands show failover and ...
Hung Tran's user avatar
  • 3,754
3 votes

Failover with two ISPs, one with public and one with private addresses

Putting aside the question of why you are using public addresses in your network for a moment, you would configure this the same way if you were using private addresses: you configure NAT (actually ...
Ron Trunk's user avatar
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3 votes
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Failover with two ISPs, one with public and one with private addresses

That depends on whether or not you need to public addresses to be available outside you company. If so, you are going to need to work with the ISPs to set up BGP routing with them. If you don't need ...
Ron Maupin's user avatar
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3 votes
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Lowest Possible Failover Latency

Failover time is going to be dictated by two chief factors: 1.) Time to detection - How quickly the connected systems can determine a link has failed. 2.) Time to convergence - Once the failure is ...
rnxrx's user avatar
  • 6,114
3 votes

Multiple ISPs failover configuration

Cisco has a good document that describes your exact scenario: Configure the ASA for Redundant or Backup ISP Links This document describes how to configure the Cisco ASA 5500 Series Adaptive ...
Ron Trunk's user avatar
  • 67.5k
3 votes

Cisco failover interface in waiting

You are not using your ASA's in a failover configuration, so you should not configure them that way. Use the command no failover If you goal is to have one primary link and a backup link, oyu can ...
Ron Trunk's user avatar
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3 votes
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Cisco failover interface in waiting

To solve this issue, you need at least a L2 switch in between. If you would like to run dual ISPs, you can use another main/physical interface and terminate it on that L2 switch too, then separate L2 ...
Hung Tran's user avatar
  • 3,754
3 votes

High availability LAN segment with Cisco ISR4451X and 2 x Netgear GS724 - Port-channel vs. BDI vs. BVI?

Configuring the router with a BVI interface seems to make the most sense. You can't use a port channel, and BDI is for IOS-XE routers. Make the router the root of the spanning tree.
Ron Trunk's user avatar
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3 votes

Network routing/WAN failover

The issue is where/what you're tracking. You need to be able to continue to steer traffic over the down route in order to tell when it comes back up. Using PBR for traffic sourced from the router (ip ...
boomi's user avatar
  • 993
3 votes

ISP Failover On A Converged Network

Depending on how your network is set up, this is certainly possible. You can configure the phones to pass VoIP on a dedicated, tagged VLAN and traffic from the internal switch untagged - this is what ...
Zac67's user avatar
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3 votes
Accepted

Virtual IP failover issue with vmware exsi ip based hashing

The ESXi's vSwitch doesn't care about IP addresses, just MACs. The "IP hash-based routing" is about L2 load balancing - which egress port is used - and has no relevance for IP routing. You need to ...
Zac67's user avatar
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3 votes

How to know if ISP network have multiple routes

Personally, I do this type of research using a number of different publicly available "route servers" or "looking glasses." Simply do a web search for "public bgp looking glass" and you should find a ...
YLearn's user avatar
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3 votes
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Bonding and switching between 2 different Links/WANs/Interfaces

I don't want to use "both" interfaces/links/Wans at the same time, instead I want to use one of them and in case it fails Bonding will switch to the other source. That is not bonding, where you ...
Ron Maupin's user avatar
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3 votes
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eBGP failover without packet drops

Modify your Local Preference inbound on the eBGP relationship to the ISP on Core2 to be greater than 100. You will also need to add a route-map to AS-PATH prepend your prefix to the eBGP neighbour on ...
ditrapanij's user avatar
  • 1,307
2 votes

Lowest Possible Failover Latency

STP, including RSTP will fail over the slowest. Routing protocols come in second place. By far, the fastest failover is a port channel. As long as even one link in a port channel is up, the port ...
Ron Maupin's user avatar
  • 99.6k
2 votes

Layer 2 Failover

If you have any kind of Layer 3 equipment in that setup, you should be able to easily do this by having both being routes to your destination, with A having a lower metric than B. This would cause all ...
Christian B's user avatar
2 votes
Accepted

Clustered Juniper devices using public DoD IP addresses for communication?

I'm not a Juniper expert, but other vendors have done something similar for heartbeats (Hey! I'm still alive!), or other reasons. There is no technical reason why that specific address range was ...
Ron Maupin's user avatar
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2 votes
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IP SLA command not available, alternatives?

The simplest way to achieve a failover is by using floating static routes. You are going to need a default route (0.0.0.0/0) to your ISPs. Cisco has AD (Administrative Distance) that basically tells ...
Ron Maupin's user avatar
  • 99.6k
2 votes

Cisco ASA 5512 (OS 9.1(1)) HA failover issues

It turned out to be Port Security enabled on ISP access switches, which was blocking frames (following failover) for approx. 30 minutes. Thanks everyone and Ron Trunk especially
Ottootto's user avatar
  • 131
2 votes

Web server address with two ISPs

Unfortunately BGP will not help you, this is small-scale. You will not be able to justify a provider-independent block of addresses for a single web server even if RIPE is still issuing them. ...
marctxk's user avatar
  • 1,181
2 votes

How do you account for unreliable ISPs?

The problem is that your router doesn't know why the traffic is coming in slowly. Maybe your ISP is flaking out, maybe the server is slow, maybe that particular data stream just doesn't have very much ...
Peter Green's user avatar
  • 13.3k
2 votes
Accepted

Cisco ASA vs Router or Both

It's hard to completely generalize any of the above. Particularly toward the higher end of the spectrum routers will move massively more data than any firewall. That said, as the speed of the router ...
rnxrx's user avatar
  • 6,114
2 votes
Accepted

Catalyst InterVLAN Routing w/ Failover ASAs

One way is create a new VLAN with 10.0.0.3 as the SVI (VLAN) interface. Eash ASA (in a failover pair) gets connected to an access port on that VLAN.
Ron Trunk's user avatar
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2 votes
Accepted

AWS direct connect with Cisco ASA redendency

Creating another VLAN is a reasonable way to go. Yes, you should use BGP to detect when one side becomes unreachable.
Ron Trunk's user avatar
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