Cisco Switching/Routing :: 2960 G / 1941 - Network Design
Jun 14, 2012
I have been recently asked to design a network. What I have for equipment is four 2960G's and one 1941 router. One switch is a root switch and the other three will have end devices on them.I have decided on three V lans to go with: VLAN20 Data, VLAN30 ISCSI, and VLAN99 Management each with seperate trunk links and redundancy (see picture below).
I have a seperate trunks for each V lan using the switch port trunk allowed. With exception to the Data V lan.My design has the Data V lan as the native because it is going to be receiving untagged traffic from the external network. I have set up inter v lan routing on the 1941 via sub-interfaces to allow them to talk to each other (or because of allowed they cannot?). I have one port coming from my router to my switch via Ethernet cable which is my bridge out. I have my external port doing a NAT translation for my inside addresses and a Default route set up ip route 0.0.0.0 0.0.0.0 gig0/0. I am using rapid- PVST to prevent loops and provide my zero downtime convergence when a link goes down. As it stands right now I cannot talk out of my network or inside of my network.
You can see it is highly redundant and I do not want to change it. This network is going to be deployed but there will never be anybody physically there to manage it which is why I made it as redundant as humanly possible.
I am in the process of planning our new network. Our business is changing from hosting its own data centre, to moving it to a professional facility. We have 120 users, over 100 servers (physical and virtual) and three sites (main premise, data centre, dr site). The new network will connect all three. Our new WAN links are almost ordered. We will be making use of a managed MPLS IP VPN, with a 100M access rate at each site. I am currently focusing on the desing of the network at the main business premise. We have a significant investment in Cisco 2960 & 3750 switches and Fortinet firewall appliances. I plan to re-use these in the design.
Our current LAN is very flat and I want to segment the network. My plan is to create a number of VLANs, enable the Inter VLAN routing on the 3750 and then attach the 3750 to the Fortinet appliance which will provide stateful firewalling and traffic policin based on the VLAN (subnet) addresses. It is important that the traffic be routed as quickly as possible from this site to our prod and dr data centres.The 2960's act as the access layer, the 3750 as the distribution layer. The 2960's will connect via port channels (layer 2) to the 3750's and the VLAN interfaces will be configured on the 3750.
I was then planning on creating a VLAN on the 3750 to connect to the Fortigate appliance with a /29 address to limit the addresses used whilst also providing some flexibility for any future design changes.I want to implement a little security between the VLANs on the 3750 switches. I have a question about this coming up.I then plan to use the Fortigate appliance to do basic traffic policing based on source/destination addresses.
The WAN routers will connect to the Fortinet appliance on a Gigabit copper interface. The WAN routers will run HSRP between themselves and only one router will be active at any one time. The failover will be managed by the Fortigate and Cisco routers.I plan to define those addresses hosted at the other data centres and associate them with the interface associated with the WAN.I will then define the routing on the firewall for the two other data centres through summary routes for each of the sites. We will run static routing from the Cisco 3750 to the Fortigate and Fortigate to WAN router. We have no other networks/sites and won't have any others in the future.
I'm looking for feedback and constructive criticism on our network redesign project for our company.We are currently on a 192.168.1.x/24 and running out of addresses. We are looking to move to the following design and implement VLANs as well for segregation and security. We are probably going to use a few SG300s for switches. [code]
remote location on MPLS circuit terminated on a Cisco router that has Internet connectivity through Central Site router. We are installing a cable modem at the remote location that is to be used as the Primary Internet Connection but still be able to use Internet through MPLS if the cable Internet goes down. We want the failover/fallback to be handled automatically.
We have an ASA5505 for the cable Internet which then feeds into the ISPs modem.
At first I was thinking about getting a module for the remote router so the cable Internet could be terminated on the remote router as well but that introduces a single point of failure. I would also like to firewall both the MPLS and the cable Internet but if I do so on the ASA there is another single point of failure.
I am just browsing and looking for a solution to converge my multi-vendor switched network and bring some redundancy to it as recently we managed to get a redundant links. I have a need to change core switch to Cat3750G, which has Per-V LAN-RSTP+ on board, but tests have shown that it won't be compatible with some other proprietary per-V LAN RSTP solution other vendor's switches use currently.
So, I thought maybe standard-based MSTP design might do the trick. I've made some tests and got some weird and unstable switching result. I have two topology rings with a core switch in the center. Every ring has about 10 switches, so practically network diameter may vary from 5 switches (when spanning-tree converges in the center and I have a blocking port somewhere int the middle of the ring) to about 10-11 switches (if a I have link failure on any of ports right at the core switch). I disconnected one port from core switch to eliminate a possible switching loop while I will be configuring new MSTP design. Then I started enabling MSTP on all the switches staring from core Cat3750G to MSTP, one by one, placing all switches to the same MSTP region, and placing all V LAN's to default MSTI0(CIST) cause I don't need to organize any separate MSTP instances for every V LAN or for group of V LAN s. When I turned MSTP on on 7th or 8th switch in the chain (cause I had a physical chain when I disconnected one port out of redundant ring) I got all switches "flapping", storming and flooding the network with broadcasts. Even when I had one redundant port disabled.
I have no idea what I am doing wrong. I noticed that Cat3750G has an option that defines a possible network diameter which actually automatically changes some hello, max age etc. attributes according to diameter specified. When I defined a maximum network diameter of 7, if didn't change anything: I still have hello timer of 2 sec etc. I've been wondering if the maximum network diameter has something more than just a "variable" to fine tune hello timers etc? Maybe I won't be able to use MSTP in my network which might have diameter more that 7 switches. Or maybe it was a mistake of placing all the switches to the same region and all the v LAN s to the default MSTI0 (CIST) and I should configure one MSTI per V LAN or per some group of V LANs and subdivide my switches to few MSTP regions?
i just need to know is is there any way to prevent network from MACflap.The best way will be when switch will disable the interface where the macflap was detected.I need to set this security feature on 2960s.
We have a 2960 switch which is connected to the core via a VLAN trunk. We have disabled broadcast port suppression but, the 2960 is shutting is shutting 2 ports down on the network and this looks like excessive braodcast. How and why would the switch start dropping traffic when the default is don't do anything? It had to be rebooted to get the port active again
I have a network coming up for a switch refresh. Management is pushing for 2960s and I would like 3850s. We are running Cisco Voice and Video over the network. I saw a few things that seemed to be in favor of a Layer 3 switch vs. a Layer 2 switch. Some items like better performance due to switching based on IP vs. switching based on MAC. Some information that will show the 3850 to be a better choice or that the 2960 is capable.
We have 2 sites, each with 2 x 4506 switches which will be connected togther using an etherchannel. The switches will provide access ports for client devices and will be configured with HSRP to provide gateway redundancy. SW1 will be HSRP active.2 metro ethernet links will be installed in each site which will connect back to our HQ sites. OSPF will be used over the backbone to provide resiliency and to allow shortest path routing to each HQ and to prevent traffic over the HQ to HQ link.
The 4506 will be trunked togther with an SVI for providing OSFP adjacency.For the traffic flow from SW2 to HQ2, traffic will hit SW1 and then route back to SW2 and then to HQ2. Is this the best way to do this? Should a second link be connected between switches just for routing or should something like GLBP be used?
I have an existing stack of 4 x 2960-S switches connected by stack cables.I would like to add another 2960-S switch to the stack but am unable to as the 2960-S will only allow 4 x 2960-S switches per stack.how I would add the 5th 2960-S switch to the existing stack of 4 x 2960-S switches.
I have a 24 port 2960-S that is not communicating with a 2960-LST that it is directly connected to over fiber. The link is up on the LST but will not come up on the -S. What command should I use to bring up this link? I have tried no shut from the (Config-if)# prompt.
I have a typical LAN environment that spans across a large warehouse. I have done a lot of redesigning of the environment to satisfy the need for a disaster recover plan. I now have created a LAN with multiple v lans and must also connect all the access layer switches back to the core switch where the servers are.
I was thinking of something simple such as Port channel of 2 Gbps across the backbone and simple floating static routes . I have then moved my wan access link to a 3750 and implemented routing a CEF at each of the 3 core switches (blue). My question is more of design.
We have remote office where we have 2921 router with 6 layer 2 switches. We have few servers which need to be in specific vlan.
2921 router does not have switching engine we are using this to support VOIP.
So on 2921 router i created 6 sub interfaces for each vlan and assign them to their specfic vlans. Then I have trunk connection to switch 1. Now switch 1 connects to all other switches in the network. As our company design all layer 2 switches should be transparent mode. i tested them i can ping from one switch to all other switches.
Router vtp mode i set to transparent mode and from all switches i can ping the router sub interfaces.
if the above design is acceptable how does the routers know which one is active and which one is standby ? if we need a direct connection between two routers they have to be on a seperate subnet and routers dont allow broadcasts - so how will hsrp work on routers ?
We are designing a LAN Network for ourselves.The proposed design is as follows:
4 x 2960S switches in a Stack Access-Stack-I 4 x 2960S-PoE switches in a second Stack Access-Stack-II
2 x 3750X switches in a Stack Core-Stack
Now I would like to connect it in the following manner ?First,I would like to use EtherChannel using the 10Gig LinksSecondly, I would like to use Cross-Stack EtherChanel too.I have given a graphical illustration of the connectivity Now my Qs: a) Will the 2960S supports EtherChannel using the 10G links and the 3750X too... b) Does the proposed solution will work... or It will have any problems.
QoS design problem that I have. I have a client that is deploying new 4507 series switches with SUP6Es. The client will be running lots of voice, streaming video, and video conferencing over the LAN and want to base QoS on Cisco Media net recommendations.
I need to design a new QoS policy with focus on the above media services with basic queuing for critical data services. I have read the Media net design guide and the suggested 12-class model will be too complex to start with but I have seen references to start with a 8-class model with the ability to easily migrate to 12-class in the future. The 8-class model meets all of our requirements but I need to understand how this will work with the 4507 queuing model? [URL]
I've been tasked to come up with a design to segment our internal network to reduce broadcast domain size. In addition, we are running out of DHCP available DHCP addresses. I need to have a solution that will give me more available IP's, but reduce our broadcast domain.
We are Cisco VoIP shop. Our current environment consists of dual 6509 chassis in a VSS config. We have 10 access switches that are model 3750's. Each 3750 has dual 1Gb fiber links to the VSS Core in an etherchannel configuration. We have 2 VLANS (data and voice) that spread throughout every switch. Both VLAN's have their own DHCP scope.
Our current broadcast domain is a 255.255.248.0, so we have over 2000 potential broadcast devices. Cisco recommends not having larger than 512. So my research has brought me to a design as follows:
MY DESIGN: > Have individual voice and data VLANs for each closet switch. > We have 10 closet switches so this would require 20 new vlans > With every separate VLAN we would need a different DHCP scope. > Configure 20 new DHCP scopes for the 20 new VLANs. > Each DHCP scope would have a 512 available addresses. > Enable IP Routing and configure EIGRP on the VSS Core and 3750's. > I'm tossing around the idea of have each 3750 be an EIGRP Stub. Not sure yet.
QUESTIONS: 1. How to verify what I described in my design? 2. Any alternative solution that might be less complicated than configuring Layer 3 on all my access switches? 3. Any thoughts on configuring EIGRP Stub vs. having the VSS Core do all the work? 4: Any template that I could base my 3750 config from?
Small datacenter design. My requirements and setup will be as follows Dell PowerEdge M1000E Blade Chassis (initially one full chassis)Dell Powerconnect 10GbE Blade SwitchesDell Compellent Storage Array 10Gb iSCSI with redundant controllersDell Powerconnect 7024 dedicated external storage Virtual host blade servers 2 x Cisco ASA for firewall (5525-X or similar in active-active configuration)2 x redundant routers or switches as gateway to public internet I am looking to be able to segregate customers (approximately 100) into seperate VLANs at the access layer and route them up to the Cisco ASA firewalls using Dot1Q trunking for segregation. The Cisco ASA's will perform NAT functionality and route to the redundant gateways. I then need to police each customers traffic at the gateway to limit bandwidth and perform specific traffic marking along with simply routing out to the internet.
Budget is somewhat restrictive so I am looking for the most "cost effective" devices I can use at the gateway to perform the traffic policing/marking/routing for each customer.
On occasion employees are downloading large files for business purposes, at very fast speeds. This has the potential to overwhelming our Internet circuits which causes our Customers problems accessing our Web Hosting services.
Our network is comprised mostly of 2960S switches for the employees. Webservers are connected to other 2960(nonS) switches and directly into the 6509 VSS.
Customer’s traffic comes in through one pair of ASA’s. Employee’s traffic is handled by another pair of ASA’s.
Employee traffic flows from the 2960’s, past an L3 SVI on the 6509, then through the Employee ASA’s, then to the ASR’s, then out to the ISP#1 or ISP#2
Web Server traffic flows from the 2960’s or 6509, to the Customer ASA, then to the ASR’s then out to ISP#1 or ISP#2. Web server traffic does not flow through an L3 SVI.
The goal is to allow employees the ability to have the most bandwidth they can, however customer traffic always has to be preferred in the event of a ISP circuit approaching its limit.
This past networkers I was at the Cisco booth discussing how the 2248 can connect to the 5548 and have server connectivity. It was told to me that now, as of a fairly recent NX-OS release, you can have the 2248 going dual-homed to both 5548 via VPC and then have a server connected to both 2248 and be in active-active mode. Is this correct?
When we first deployed our 5548 and 2248 we had to put the 2248 in a straight pin mode, where it only had connections to one 5548 and then the server would dual connect to the 2248's and be in active-active mode. I was told that this changed with an NX-OS release however documentation still seems to be fragmented on what exactly is the case.
I have a question for Cisco Cat.2960-s Flex Stack switches which are installing on our sties. Two of 2960-s Stack switches as access switch and two of Cisco ME 3600X Series as distribution layer switches are to be installed in our sites. In case of two stack switches, One is will be a Master and the other one will be a member logically, as you know. So, if the master fails, the other one automatically becomes the stack master following a well-documented election process.
Now, it is my question. How long takes to be a stack master from a member switch ? I cant find it on white paper of Cat.2960-s flex stack . And also, I heard that sometimes a member switches don't election process when the master fails as a result, all stack members become a panic. Is that really right ? In addition, I heard that the stack switches have many troubleshooting points than stand alone switches. I really wanna know if the stack switches are good solution for resilience of huge network site. I'm waiting an answer from those who have experience of maintenance or installation.
I would like to do the following architecture with the same C3750 : network X,Y,Z connected to 3750 in VRF D the 3750 uses a routed interface on subnet E for the default route in VRF D on this routed interface a BYPASS EQUIPMENT the other BYPASS EQUIPMENT interface is connected also to another routed interface on subnet E "also" this routed interface is in another VRF C with other network A and B.do you know if it will work because of 2 routed interfaces on the same IP subnet or is there a way to do that ? the only goal for me is to catch traffic from network X,Y,Z on SYN and ACK.
We have our network setup as displayed in the attached. We have 2 HQ offices and 1 branch office. The branch office needs to connect to resources located at both HQs but taking the most effecient path. We have ethernet circuits connecting from each HQ to 2 x Cisco 3560 switches in the branch. HSRP has been configured on the 3560 switches with SW1 as active and SW2 as standby. OSFP has been configured in a single area 0 and the path cost on the link between HQs has been increase to allow 3560 SW1 to route to HQ1 directly and HQ2 via 3560 SW2.The 3560s are connected with a trunk with a L3 SVI for OSPF. This seems to work ok but I have noticed that the branch could become transit if the HQ1 to HQ2 link breaks. How can this be avoided? I realise that if we configure the branch subnets and SW1 to SW2 link in a stub area (area1) then all traffic will route from SW1 to HQ1 and will never share over SW2. I'm assuming that this is because OSPF chooses inter-area routes over intra-area.
I'm working designing a switch system for our core/data center.
We have 5 esx hosts, 2 sans with 3 nodes each. We have voice servers, a couple of routers and a few odds and ends. There are 7 other locations aggregating into this data center via 1-2gbps fiber connections. The bandwidth usage on these links is minimal, but there is a total of about 3000 devices aggregating into the system. My main concern right now is the 3560G's are seeing many output drops, due to the small buffer size on those switches. I have been looking at couple of options to resolve this issue, including the 4948E, 4507E, and 3750X switches.
Budget being the biggest factor, I am finding that the 4507 might be out of the price range. So I was leaning towards the 4948E switches for connecting the servers and iscsi san's as the 3750X is not recommended for iscsi. Redundancy is important so I would like to have two. The second concern is that I need to aggregate the fiber connections and for that I was looking at the ME-3600X or possibly the WS-C3750X-12S-E. I'm running eigrp, so this switch would need to have full routing, as it would also serve as the core switch for the 4948E's.
So in the end I was thinking that two 4948E switches up linked to the ME-3600X which would do full routing for the fiber aggregation and any routing needed for the servers and sans.
Servers and Sans_________4948E________ME-3600X_________7 fiber connections |____________4948E_____________|
I would look at a second ME-3600X in the future for redundancy. This is the lowest cost biggest buffer solution that I could find.
I have a 1941 router configured for Policy based routing with two ISPs.Two static default routes configured to point the gateways of respoective ISPs with same metric.But the problem is, packets are going throug the one ISP only while doing traceroute.
ISP1-----> <----------------------> LAN1 | Router | ISP-------> <----------------------> LAN 2
Below is my configuration :
Current configuration : 5958 bytes ! ! Last configuration change at 05:18:56 UTC Mon Jun 25 2012 ! version 15.0 service timestamps debug datetime msec service timestamps log datetime msec no service password-encryption
How I can prioritize Web Ex, Skype and some two websites on Cisco equipment. My set up is such that my 512kbps link goes to a Cisco 1941 router>Cisco ASA 5505>Cisco Catalyst Switch 2960>Computer.I want to be able to prioritize this on my network and test that it actually works.
We are about to install a new network consisting of Cat 4500s with Sup7E at the Access Layer, with Nexus 7000 at the Distribution and Core layers. We have 14 floors with at least three 4500s on each floor. Within the office block where the Access Layer and Distribution Layer reside we need to support secure borderless networking using 802.1x to place users from different parts of the business into segregated networks at layer 3.All switches will have the feature sets to support MPLS/ VRF / OSPF / EIGRP / BGP etc.We quickly dismissed the idea of using VRF-Lite due to the sheer number of Vlans we would need to managage and maintain, the point to point links alone just to get one additional VRF on each floor required far too many Vlans.As a result we are now considering deploying MPLS. The obvious benefits include scalability and manageability, the fact that all switch to switch links can now be routed, instead of having to using SVIs.
I have this Cisco 1941 router with two Ethernet ports g0/0 and g0/1. The g0/0 is connected to office LAN with internet access. As my office LAN is DHCP, it will assigned a IP address for g0/0 since this g0/0 is configured as "ip address dhcp". Now my question is that i have a group of 5 pcs, namely PC1, PC2, PC3, PC4 and PC5 that is connected to the switch and one of the ports of this switch is connected to g0/1 of Cisco 1941. Is it possible that let say PC2 and PC3 (both DHCP enabled) could access the internet access from g0/0 and at the same time, the office LAN assigned IP address for PC2 and PC3 automatically?
Office Lan with internet access (DHCP) (Default gateway 10.0.0.1) | | g0/0 (DHCP enable) (DHCP assigned IP address 10.0.0.138) Cisco router 1941 g0/1 | | HP Switch | PC1 PC2 PC3 PC4 PC5
Is this operation possible? if possible, how to configure inside the router 1941 to achieve this objective?
I have just set up my Cisco 1941 router to my cable internet connection. I have access to everything, but I cant login successfully into Cisco CP.
I set up a new user with level 15 privileges and a secret password. I go to login via webbrowser and I put in my credentials, but I get rejected. I have tested the username and password via the CLI, and it works fine, I just cant seam to login to Cisco CP.