Cisco Switching/Routing :: 3750 Receiving CDP Packets From Switches Not Directly Connected
Jun 27, 2010
A specific switch port which happens to be part of a 2 switch 3750 Switch Stack is seeing multiple CDP packets from 3 extra switch port interfaces that are not directly connected. Noteworthy is that the far end devices have the correct CDP entries and I physically confirmed at least two of those connections that lead to the switch "upstream to the culprit switch". Tricky part is that its production so room for maneuvering is limited. At some point I disabled all Ports save for the real uplink and the problem momentarily disappeared. Re-enable the interfaces problem resurfaces. Is there an explanation, technique to eliminate the culprit with minimal disruption?
I recently moved house and got a new ISP. I followed their instructions and set up my broadband. connection is working fine through the LAN, and I can connect to the wifi on my phone but when I try to connect my laptop via wifi it says it's connected but I can't access the internet and it looks like it's sending packets but not receiving.
I have client who has two distant offices with 3750 L3 as core (do all vlan routing for local office) and multiple L2 access switches with multiple VLAN’s connected to it. First 3750 is hub also connected to internet, second 3750 is spoke and acting as a router on stick. We have eigrp configured on both side ISP provided client 100Mbps link as a trunk with two vlan; vlan10 for voice and vlan20 for data. We assigned two small subnets to these vlans 10.15.17.0/29 and 10.15.17.9/29. Hub addresses are 10.15.17.1 and 10.15.17.9 respectively. How to force voice over VLAN10 and data via vlan20, but still do some load balancing? How to setup default route on second (router on stick) switch?
I have 2 PE routers connected to each other via 2960S and 3750 (non-metro) switches:
[PE1] -- [2960S] --  -- [2960S] -- [PE2]
I will be sending voice and data traffic between the two and my voice traffic will be marked DSCP EF & EXP 5.
Since the 2960's and 3750's can't match on the EXP bits, I am wondering if the "mls qos trust dscp" command still works. Is the 2960/3750 able to match on DSCP even though there's an MPLS header on top of the IP packet?
I'd like to avoid having to tag my VLAN traffic on the PE and rely on COS to achieve QoS in this case.
I am troubleshooting a fiber connectivity issue.Now I have two switches, one is 3750, and another is small biz 300 series switch. Both switch has a single mode smf gbic. Now I have two swtiches face to face and connect with a single mode cable. Do you think if I would get a link light on? Both ports are no shutdown.
I have a CAT 3560 connected to a ISR 2911 The 3560 has 2 subnets ( 192.168.1.0 /24 and 10.10.10.0 /24) The 2911 has interface GigabitEthernet0/1 on the 192.168.1.0 /24 and another GigabitEthernet0/0 on a WAN connection 172.16.7.246 I need to NAT both the 192.168.1.0 /24 and the 10.10.10.0 /24 to the single address 172.16.7.246 I have to use route-maps . I have IPSec VPN's and ZBF on the 2911 My problem is the NAT does not work for the 10.10.10.0 /24 network!Why?is my only option to use trunking between the 3560 and 2911 and subinterfaces on the 2911? I want to avoid sub-interfacing.
============================================================= On the Cat 3560=====================!vlan 40name the 192.168.1.0 /24 subnet!vlan 60name the 10.10.10.0 /24 subnet!interface FastEthernet0/7description Connection to Router Gig0/1switchport access vlan 40!interface FastEthernet0/16description Connection pc host on the 10.10.10.0 /24 subnetswitchport access vlan 60!interface Vlan1no ip address!interface Vlan40ip address 192.168.1.4 255.255.255.0!interface Vlan60ip address 10.10.10.10 255.255.255.0!ip classlessip route 0.0.0.0 0.0.0.0 192.168.1.1 =========================
The host on the 10.10.10.0 /24 network has the 10.10.10.10 address as it's default gateway The host can not access the WAN thru NAT....
My Data Center has one single core switch where is connected several servers, one port is the link to the router wan and other port is the link to the FW, my boss wants to install 2 nexus in order to replace the single switch. All my network has only one address, for example 192.168.10.0/24 if I connect two nexus 7010 in VPC and Domain, each nexus is going to has 2 modules with 48 port 10/100/1000 rj45 and i wan to connect servers directly to each nexus, with this figure i'm going to have a group of servers connected in two different nexus, Do they can have the same network 192.168.10.0/24 considering that the nexus are in the same vdc and vlan and have only one gateway for both groups? If the answer is positive, which nexus would be the gate way for that address, the primary or secondary? Or i must have a different address for both group of servers, i mean for example 192.168.10.0/24 and 192.168.12.0/24?thus each nexus would be the gateway for that new address?
To have two nexus connected by VPC in a Domain mean that one computer connected to one nexus can share the same address or vlan with other computer connected to the other nexus????
We have a 3750X VTP Server and the rest of the switches are clients.
Due to cabling issues, we have a switch (Switch F) that we can't connect directly to the 3750X so we have it connected through another switch. Everything is set to VTP client with the correct domain and password but this not-directly-connected switch isn't receiving any VTP VLANs.
Anything I need to do on Switch D so that Switch F can receive the VTP updates?
I have a Cisco 7206VXR running 12.4(24)T3 IOS. It is configured with WCCPv2 using L2 mask redirection. I am using service groups and associated extended ACLs to select which subnets I want to redirect port 80 traffic from.
It is working fine for the subnet 192.168.1.0/24....
int gi0/2 ip wccp 10 redirect in ip address 192.168.1.99 255.255.255.0
... however, there is OSPF running between the router and a Mikrotik device directly connected to this interface. The gateway addresses for all the client subnets are on the Mikrotik. Traffic from other subnets, e.g. 192.168.2.0/24, 192.168.3.0/24 come in on this interface and I want to redirect those too. But it appears that the redirection doesn't work for those subnets (I don't see any hits on the relevant ACL for any subnet except 192.168.1.0/24).
It seems like the router only wants to redirect traffic for subnets that it has an IP address in itself. Admittedly, all of the example configs i've found on cisco.com are for redirecting traffic from directly connected subnets but I can't find anything that denies thie possibility of redirecting any traffic that comes in on a given interface.
The question is, is this how WCCPv2 redirection works? i.e., the router must have an IP address in the subnet to be redirected?
Since last week we started noticing this problem that the branch users started to complain of slow application response.. After verifying it with the ISP and middle network we noticed that if i ping from my machine (ie usernetwork) to the WAN Router interface (facing the ASA) , i get time outs.. which is strange cause this is directly connected to it via ethernet cable.
In fact i receive traffic on a one client per vlan basis (traffic is PPPoE), i receive all this traffic on a router, collecting all these vlan on a bridge where the pppoe packets are treated.When I use a transeiver to convert operator fiber arrival to my router copper media interface, i have no problem....
When I use dot1q-tunnel to make the same on my 3750, packets seems to be corrupted.I get PPPoE timeouts and packet loss, not regulary, totally stochastic...
I made dozen of tests and different settings, without success I first thougt of MTU issues. [code] I made tests with system MTU and/or system jumbo MTU above 1500, without success.I didn't found any known caveats on 3750 running Version 12.2(25r)SEE4 related to dot1q-tunnel.
I have an Cisco 6500 CS and there is a Cisco Unified Communication Manger Server connected directly to the Core Switch.I tried to change duplex and speed ( fix and auto ) for both sides, but the same problem.
I am trying to test (if possible) the idea of having 2 6509-E switches connected directly to each other while using VRF-lite (Sup 2T). The idea is to have 3-4 separate networks. For example Net-A, Net-B,Net-C, Net-D. There is no PE router*, just these two switches. Also, there sin't any other access layer switches. All users connect directly to the 6509-E's via switch 48 port switch blades.
Net-A and Net-B on separate VRF's, but able to talk to each other. Net-C and Net-D* on separate VRF's without being able to talk to any other. Net-D* will have a PE since it comes from an external network. This is something I would like to test in a lab environment, but I am not familiar with VRF's.
My C6500 is having relatively high CPU (no spikes, but constantly)
I'm under the impression that cef is causing this problem because alot of packets are being processed or send to/from the CPU. [code]
I did a netdr and I can see that the majority of packets going to the CPU are packets for which I have an entry in the CEF table.What can be a reason why those packets don't get hardware switches?I'm running Version 12.2(33)SXH5 - Sup720-10G.
We have a remote site that is using 3750X switches as layer 2 switches back to our home site. The uplink port is showing dropped packets but the utilization on the link is never about 10%. We have a 100Mb circuit to this site. Our speed tests and iperf tests are not showing any issues that we can see. However the port is still droping packets. It is not dropping at a high rate but they are dropping.
If I have two stackable switches one switch uplinks to one 6509 core switch and the other connection uplinks to another 6509 core switch, and also the other stackable switch does not connect to the core switches. Because I am using hsrp and also we are not using vss then one uplink to the core is not in used only ones is so then how does creating an etherchannel between does two uplinks to both core switches benefit me in anyway such as more bandwith and using both uplinks at the same time or I'm I wrong?
If I have two stackable switches were only one stackable switch has two uplinks one uplink goes to one core 6509 switch and the other uplink goes to the other 6509 core switch can a Layer 3 etherchannel be used if each uplink go to a different core switch, by the way hsrp is running between both switches and also can you give an example how data will be routed from the stackable switch through the ethernetchannel to one of the core switch accross the WAN to another core switch?
One Day the internet is fine the next day The Internet Stopped working. The problem is my pc is sending packets but not receiving any i though it was a bug or something so i restarted my pc after i restarted my pc the internet was working fine until a couple of minutes passed it stopped receiving packets again.i tried resetting the modem but nothing worked.I tried winsock fix or resetting TCP/IP and stuff but nothing workscause its starting to frustrate me.
Our computer is sending but not receiving packets. We've tried 3 different wi-fi adapters, and that wasn't the problem. We have no idea what's wrong? It won't pick up any wireless signals by the way, and it works fine while connected via Ethernet.
I have a home network that does not connect to the internet, but which I use to play games on, or did before this issue happened by.For years my PC's and friends ones had been able to connect into the network with little or no problems, but a few months ago my tower PC just stopped picking anybody or anything up on the network and I have tried tons of different resolutions to solve this.Anyway, the other day I bought a new HD and installed XP SP3 again on it, and for about fifteen minutes I could connect to my Vista Laptop and share files and play games, then it stopped.Next day the same again and off and on till now when its been down for the last week.I have also now bought a new network card - no difference - and disabled the on board network card through the BIOS - no difference.I have done a Winsock repair, replaced automatic IP addresses with manual ones, and countless other remedies which have not solved diddly.
I have a windows 7 laptop and i have bridged my wireless with my ethernet port on it, i have directly connected my ubuntu server to my windows 7 laptop via crossover, and ubuntu says its connected, but it will not recieve internet. I can get 2 windows pc's to bridge successfully, but not a linux machine. Is there some configuration im missing or something that i missed? the goal is to get internet for my ubuntu server.
I have a Asus EEE PC 900 laptop running Windows XP Home. I DO NOT use a modem or router. I connect wireless to someones network (which of course i dont know who it is or how far it is from me) I connect to a Linksys unsecured network. I get good to very good (some times excellent connection from it) The name of my adapter is: Atheros AR5007EG wireless network adapter.Two days ago i was on the internet, and all of a sudden i Lost service ( usually when this happens i wait it out and it comes back)But it hasn't.So I'm checking through my settings and i noticed that im sending way more network packets than receiving. Last i checked it was around 40,000 sent and 5 received. So I wait and wait and wait and the most packets it would go up to is 90 while as sending is still in the thousands.It also says im successfully connected with good to very good connection status (but yet i cannot surf the web because i do not have enough network packets)
I tried different locations in my house (that didnt work)I uninstall and reinstalled my network adaptor (that didnt work)I turned off and on the wireless switch(that didn't work). Im wondering if this has something to do with my laptop or the other persons network? how can I increase the received network packets?
I cant connect to the internet. When I use other networks its fine. Also all the computers in this network im trying to connect to can connect and work perfect. I know i have the WPA code right. Its sending but not recieving any packages. The IP address 169.254.140.90 so i know its not working right.
Everything is fine except that whenever I am receiving packets, there is a corresponding upstream of packets which is subsequently slowing my download speed.I should be getting ~600kbps, but I am instead getting ~200kbps.The ratio of packets sent/received is almost 1:1.5, and of course when your upload bandwidth is being maxed it starts cutting your download speed.
I have a laptop computer with windows 7 and im having trouble connecting to my wireless internet. It says that im receiving packets but not sending them. I have tried to troubleshoot the problem and it says that the default gateway is not available. I am not sure what is happening with it, it started having problems while at a starbucks, and now the wireless and the LAN is not working on it.
I have 2 Cisco Catalyst 6509 switches connected directly using direct point to point link.The OSPF is configured for point - point link.The currently the interface is down administratively.I will unshut the port . After that i would like to know how much time will it take for the ospf to establish the neighbour relation.
i have an acer aspire 5315 and im running windows vista home basic, My wireless has had no issues at all until i came to oklahoma yesterday and my internet will not connect to my dads wireless, but at my moms it had no issue, and at the airport i connected to there wifi with no issues also, is there some kind of setting that gets changed when you connect to the internet in the airports that wouldnt allow you to get on your internet at home?
In my customer having 3750 switch and they have simply assign IP address for vlan and enable telnet in switch and other things are same as default switch.In this switch they have connected 8 cisco layer 2 switches(6 managed and 2 unmanged switch) and approximately 5 servers connected in this switch.In a particular interval,users accessing File server are connected to 3750 switch become hanged for few min.This happen for some particular interval.users accessing this server becomes entirely hanged for few min,then i have configured port monitor cmd and i have installed one wildshark tool to host connected directly to that switch.
I am using a 3750 as a default gateway for multiple Vlans on a few 2960 switches. The trunk lines are configured and working and I have assigned ip addresses to each of the Vlan interfaces on the 3750. My issue is that I can only ping the ip address on the Vlan interface of the 3750 if I have a working computer plugged directly into the Vlan on the 3750. I only have 3 vlans on the 3750 that have hosts directly connected (vlans 2, 10 and 40) the other vlans ( 20 and 70) don't have any clients plugged into them on the 3750 but the hosts reside on 2 different 2960s that connect via trunk ports. How do I keep the vlan interface on the 3750 switch pingable when I don't have hosts directly connected in that vlan on the 3750? (yes, I have enabled ip routing on the 3750)