Cisco Switching/Routing :: WS-C3560CG-8PC / IP Connectivity Without Route Or Default Gateway
Sep 19, 2012
Recently we observed that newly installed WS-C3560CG-8PC access switches are able to communicate without a default route or default gateway.The 3650 switches are used as a layer2 access switch behind a layer3 distribution/core. They have only the management VLAN configured for IP with a single address.
The ARP table looks like there is an implicit proxy-ARP request sent for any IP address.
We definitely have no configuration whatsoever which would explain this.
Is this a new feature? We don't observe that with the older 2960-series...
Here is a brief trace of what's happening (debug arp):
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 220.127.116.11, timeout is 2 seconds:
Sep 20 14:44:06.706: IP ARP: sent req src 10.1.8.41 1833.9dc9.wxyz,
dst 18.104.22.168 0000.0000.0000 Vlan1
Sep 20 14:44:06.711: IP ARP: rcvd rep src 22.214.171.124 2c54.2dd3.wxyz, dst 10.1.8.41 Vlan1..
The mac address if of course the mac address of the layer 3 interfaces of the distribution switch, no surprise here (proxy ARP is turned on by default).
Why is the 3560 sending out proxy arp requests without being told to? As far as I understood proxy ARP on Cisco IOS it only means it will reply to a proxy ARP request but will not send out proxy ARP requests by default.
I have a Cisco 2960 ( WS-C2960-8TC-S) running 12.2(46)SE C2960-LANLITEK9-M image.I would like to set an ip route 0.0.0.0 0.0.0.0 126.96.36.199 but the current image does not allow.Will ip default-gateway 188.8.131.52 work or do I need ip routing ?The ISP has provided a /30 address and we are using an additional /29 for our network devices. I dont think this image can be upgraded. I need to forward routes directly out to ISP. [code]
I have a 3560G and an ASA FW, for which I am trying to use PBR to append the next hop. The gateway is the switch VLAN address and the amended net hop is the same VLAN interface on the ASA. Trouble is, I can ping the FW from a client, but not the switch. If I remove the route map, I can ping both. Even more strange is this is the case for some VLANs, but not all!
HOST ON VLAN 96 IP 10.11.120.99 S/M 255.255.255.240
after reinstalling Windows XP SP3 my Local Area Connection just cant connect to the internet, it just keep saying Limited or no connectivity, which have never happened before after a fresh Windows XP SP3 install. I'm using wired connection, cable goes from my BT Hub to my desktop. I've tried different cat 5 cables, reintalling network driver, all those ipconfig /release, /renew,/flushdns, netsh int ip reset log and so the list goes on.... I've tried lspfix.exe & Winsockxpfix.exe and none of them fixed my internet connection. I've also tried safe mode with networking to see if ill be able to connect to the internet but still no luck. Below is a netsh int ip show config & ipconfig /all commands:
Microsoft Windows XP [Version 5.1.2600] (C) Copyright 1985-2001 Microsoft Corp. I:Documents and SettingsOwner>netsh int ip show config Configuration for interface "Local Area Connection 5" DHCP enabled: Yes
We have recently purchased a Cisco SG300 and have been configuring it. [code] The VLANs have ACLs set up to prevent any communication between the Holly and Tempo VLANs (and their associated WAN VLANs).Each VLAN has a WAN available for it's use, which connects to external networks (including the Internet).In order to facilitate this, we have set up all the necessary ACLs and routes and confirmed that this all works.However, the problem comes when we assign the static routes that specify the default gateways.We add the two static routes below:
-0.0.0.0 next hop 10.10.200.254 metric 1 -0.0.0.0 next hop 192.168.200.254 metric 1
In this case, only one of the VLANs has WAN access. It is either Holly or Tempo (it can be either if the order the static route is added is changed).What we need is to force Holly to use Holly WAN and Tempo to use Tempo WAN, but we cannot see a way of doing this.Effectively, we want the following static routes: [code]
I have a MPLS cloud in our data center. I want one network coming into our core router to have a different default route than the other networks coming in. I'm getting hits on the acl but the route isn't applied and goes to the default route that is configured in the router. I have other PBR for setting local-preferences and as-paths and they are working fine.
The router is a 7206 Version 12.4(11)T3
! ip route 0.0.0.0 0.0.0.0 184.108.40.206 ! ip access-list extended 2nd_Default_Route
I'm working on a little OSPF setup in my lab and having a problem pinging out to the internet.I have a setup with (3) 3550's running ip routing. I'm configuring OSPF but I can't ping the internet from any L3 switch except the switch with the actual uplink to the internet.[code] From SW2 and SW3, I can ping SW1 on all IPs (192.168.1.90, 10.10.10.1, 10.10.10.5) but I can't ping 192.168.1.1 which is my gateway to the internet.
I have a 3750 at a branch running EIGRP connected to two routers that both have configured:
access-list 1 deny 0.0.0.0 access-list 1 permit any access-list 2 permit 0.0.0.0 access-list 2 deny any
router eigrp 1distribute-list 1 out FastEthernet0/0distribute-list 2 in FastEthernet0/0
Due to this recently applied config the switch become unreachable from the outside and cannot ping anything. Everything connected to it works fine. I was able to remote into it from a switch behind it and noticed that the 3750 has no default route in the routing table. I do see a default route in the eigrp topology table. How to make the switch learn a default route maintaining the existing configuration on the routers.
imagine I want to make VLAN200 workstations communicate like the show in the attachment. What would be the default gateway to be configured in the workstation? If I configure 192.168.1.1 as the default gateway (R1 interface fa0/0) is this right?That could be possible because the switch should be configured with command "ip default-gateway 192.168.1.1"?
I just got my Cisco SG300 28, but I have some problems getting the routing to work. I get the vlans to get to the router, with the default route. But not getting them to talk with each other. I can ping the IPs from the cisco, but I am not getting traffic to go from vlan 1 to vlan 2. When I try to google, it say that it should do it automatically, and I found no setting for it. It looks like it not creating any route for the interfaces.
Cannot set route map on interface vlan. which in non default vrf on Cisco 3750.IOS c3750-ipservicesk9-mz.122-55.SE.bin sdm prefer route in enable ip vrf users rd 200:0 route-target export 200:0 route-target import 200:0 interface Vlan201 description Users 1 ip vrf forwarding users ip address 10.31.76.1 255.255.252.0 ip helper-address 10.31.4.57 route-map fromuser permit 10 match ip address fromuser set ip next-hop 10.31.128.155 When I enter "ip policy route-map fromuser" to interface Vlan 201 I heve the message:
% Remove VRF configuration from interface Vlan201 first
I have two ISPs. Each is on it's own subnet connected to the 6509 MSFC/Switch. FW1 is on 220.127.116.11/30 and FW2 is on 18.104.22.168/30 subnet. My goal is route all traffice going to the Internet from subnet 10.133.3.0/24 to FW1 and all other subnets across the organization to FW2. I am not sure if I need to use ACL / Static route combo, or just a static routes or ACLS?
This would probably sound like a stupid question but it took at least 2 hours of my time so far. I have a 3750 switch where a router and a server is connected. From the switch I can ping the router and server with no issue (directely connected). But from the server I am not able to ping the router. The router and the server are in the same subnet. The router is configured as the default router for the server. I am not able to ping the server from the router either. Here's the output of the ip route from the router. The server IP address is 10.1.200.21 and the router IP address is 10.10.200.1
10.0.0.0/8 is variably subnetted, 8 subnets, 3 masks C 10.1.30.0/24 is directly connected, FastEthernet0/0.30 C 10.1.20.0/24 is directly connected, FastEthernet0/0.20
I have a bit of a mystery on my hands. I had a whole campus of Cisco 3750's cache a new default gateway. Example
Cisco3750#sh ip redirects Default gateway is 10.10.10.1 Host Gateway Last Use Total Uses Interface172.16.0.5 10.10.101.179 0:00 185749 Vlan1172.16.0.76 10.10.101.179 0:01 47254 Vlan1192.168.0.154 10.10.101.179 0:00 183090 Vlan1
My question is what generates a IP Redirect packet or how does the switch know what to change the gateway to? As in my case the changed gateway was a dead IP address. So I am at lose how this happened. I this case the Host IP's are network management servers conducting polling.
I plan to buy WS-C3560CG-8PC-S (Catalyst 3560-C) for my home lab. I just created a new account on [URL] (I did not register any equipment or contract for that new account). I was able to download ios 12 and 15 for that switch.- Will I be able to flash one of these versions when I will have the new switch ?Cisco warranty for these Switchs (Enhanced Limited Lifetime Hardware Warranty,[URL] says NO OS Software Updates included. Does tha mean that I can download ios updates but won't be able to flash the device or use it ?- Do I really have to buy Smartnet support to be able to update ios for that switch ?
A check out a network segment and want to know why SwA has a static route to SwB if SwA already has a Default GW to Core?
(SwA, SwB - Catalyst3560, Core - Catalyst4948)Note, there are distribute list on SwA - it does not has any OSPF route (exclude O*IA).
Does this mean when SwA send out packet with DA 10.5.64.0/26, Core will use only L2 switching (instead of L3)? Is this more effectively for Core Switch?
Pleace check my reasoning: 1. When use a static route: SwA receive packet from Vlan 20 with DA 10.5.64.0/26 it will strip out Dest. MAC and replace it with MAC of SwB. Core will switch this packet to SwB based on mac add. table (l2 switching)
2. When SwA has only Default gateway and receive packet from Vlan20 with DA 10.5.64.0/26 it replace Dest. MAC with Core MAC. Core receive this packet, lookup route table for 10.5.64.0 entry and forward packet base on this.
Last week we had some forwarding issues with our cat 6509e VSS pair, wherby clients could ping the gateway but couldnt route through it! we identified this as being core 2 in the vss pair, yesterday we rebooted the 2nd switch and now the issue has been resolved.
I'm trying to configure an IPSEC VPN + tunnel for multicast data. When the default gateway is set on the router (1841) it works fine but if I only set a route to the IPSEC peer via our gateway then the tunnel fails to come up. The end point is to a 3rd party. [code]
I found that if I add a static route for the tunnel destination via fa0/0, the public facing interface, the tunnel comes up..ip route 10.23.4.2 255. 255. 255. 255 FastEthernet0/0
and I can then ping the tunnel IP at the far end - 10.23.0.5.Why would that be? Is there a better way to do this without using a default route??
I have a design hurdle that I cannot seem to cross. I have two sites and I need the same VLAN to span both sites. I have accomplished this using L2TP but my issue is that I can no longer assign a gateway for this VLAN on the router. The 2 routers are 2821's and are connected with a dedicated fiber run.
Ant recommendation for how this could be accomplished? It would be great if I could have the same gateway at both sites by leveraging some sort of bridged interface (BVI so I've heard) but I am at a loss as to where I should start with this. Also, this is not the only VLAN that needs to traverse the link.
Using Network Assistant in XP, plugged ethernet cable to first front port and keep getting "Failed to get Default Gateway. Check your security settings to make sure the current Java Virtual Machine is not prevented from running commands.", I have tried reducing secruity to nothing but I still get the same problem.
I also have an official cisco console cable and tried that, but Hyperterminal just does not pick it up when plugged in. I have left the IP dynamic, turned off all netowork adapters apart from ethernet, set the baud rate etc... correctly, still no joy.
We have a Cisco Catalyst 4506 running: "Cisco IOS Software, Catalyst 4000 L3 Switch Software (cat4000-I9K91S-M), Version 12.2(25)EWA14, RELEASE SOFTWARE (fc1)" I have configured the default gateway as: ip default-gateway X.Y.116.65, However, when I do, "show ip route", it only shows the 3 connected networks and states "Gateway of last resort is not set". The Command "ip classless" is not set. I read on some blogs that this might explain the issue. However, when I go into config mode (config t), I get the following output.
I had setup a lan infrastructure with 5 3750 stack swithes. In these 3 of them are in one stack which is acting as access switch, 2 of them in another stack which is as core switch where all the SVI is configured. Now, when i tried to ping from our edge pc which is connected in access switch to default gaeway, which is configured in core switch, the ICMP is getting delayed . But when try to ping from the same edge pc to another user PC, it is getting less tahn 1 millisecond icmp replies.
why icmp is delaying to default gateway , but working with another edge to edge pcs without any delays?
We have two MPLS circuits managed by two different suppliers, one carries VOICE the other DATAWe are to decommision the VOICE MPLS and have increased the bandwith of the DATA MPLS to carry VoIP traffic too.
At both of our sites A & B ,devices connected to the LAN have a default gateway of the VOICE providers Cisco 2600 router , which then goes into the LAN switching. (see diagram)So what I am trying to achieve is toto simply replace these 2600 routers from the VOICE MPLS provider with our own so we dont have to change the default gateways at both sites. Testing
Our Cisco 2600 routes are plugged into each LAN switching environment with two subinterfaces configured, one for voip and the other for dataThe problem is from the router and respective subinterfaces we can get to the other sites destination without any issue, but if for example a user is at site A with Ip address 10.16.11.12/16 they cant ping the VOIP subnet at site B 10.3.11.0/24. But If a ping is issue from the Site A test router then the 10.3.11.0/24 subnet is reachable but only on the 10.3.12.0/24 configured subinterface.So i guess what Im saying is 10.16.0.0/16 from the LAN needs to be able to get to 10.3.11.0/24Note at site A 10.16.0.0/16 & 10.3.12.0/24 can communicate no problem and at site B 10.207.0.0/16 & 10.3.11.0/24 can communicate no problem.We are using IP routing, should we be using route-maps?
We have a 6509 series of core switches and 3750 series of L2 switches, There is no default gateway or any static routes to any IP.VLAN 1 is made admin down and another vlan is used for all communication here in this environment
Attached is configuration for reference But still I am able to take telnet or SSH. I want to know how telnet or SSH or tacacs authentication happens without any static or default route.
I put a QoS in a WS-C3560CG-8TC-S version 12.2(55)EX2. in our lab file upload or download speed much reduced and drop the packets with QoS everyting is fine without QoS
Here is the config: My question is why I speed reduced a lot and packets to be dropped with QoS.everything is fine WITHOUT QoS.
class-map match-any VoIP description Voice IP Phone RTPmatch access-group 157 class-map match-any WEB description Internal Web, SSL Web, DNS query, Pinnaclematch access-group 153 ! policy-map QOSMARK class VoIP set dscp ef class WEB set dscp cs3
It has ip helper configured that points to DHCP.From 4500 switch port - port x connects to 2960 port.Port x is configured as trunk between 4500 and 2960.
2960 config vlan 10 name data
All user ports are configured under vlan 10 and as access ports.Port x is trunk port connected frpm 2960 to 4500 switch allowing vlan 1 and 10 only.This switch has no default gateway configured.
We connected user PC on 2960 switchports and they were able to get the IP from DHCP server and were able to access the network? My question is how users on 2960 switch are able to access the network without ip default-gateway configured on 2960 switch?
We had a core switch (4503), distribution switches and access in our network and consists of many vlans. Almost all vlans uses DHCP Pools. But for few vlans DHCP is not yet configured. Recently one of the rogue user in vlan 1 gave the corresponding interface vlan ip of core switch (gateway) as his ip and caused a prolonged network outage for the vlan. Any way we are going to seggregate vlan 1 into different vlans, but before that we need a temporary plan to block such kinds of attack.What are the possible ways we can avoid the network outage problem even if a user gave the gateway ip to the machine?