Cisco Switching/Routing :: Enabling Flow-control In 2960s?
Nov 12, 2012
I met a strange problem after enabling flow-control in 2960s.my enviroment,
- 2 cisco 2960s 24ts-l have been created a stack
- IOS is 12.2(58)se2
- all ports have been enabled flowcontrol receive dersied
via show flowcontrol, I can see each Gigabyte Port have been enabled "flowcontrol receive desired" but, when I do the following tests
- connect equallogic ps4000xv to the port 21, I found the status of port is "input flow-control is off"
- connect one server with Broadcom Gigabyte Network adapter, which has been enable TX ON RX ON, or Auto, the status of the port is still "input flow-control is off"
I guess, the port status should be ""input flow-control is on". Test them with another port, I got the same result. why?
I've been digging into some performance issues on a LAN that has a couple of 2960s. The monitoring software I'm using has indicated a high amount of discarded outbound packets (up to 5%). The suggested resolutions were to enable flow control.
My question is does enabling flow control on all ports interrupt network traffic at all? this is a production network so I had already planned on doing it during off hours but also wanted to know if I should be prepared for any significant drop in traffic.
I would like to enable port security to hardcode the MAC address on the ethernet switch. There are 5 ethernet ports in the same ethernet switch to be assigned for one person (one note book), e.g. port 5, 6, 15, 16 and 23. The model of ethernet switch is cisco 2960S and one MAC address is configured on 2960S.
1. Does 2960S support this requirement to allow input the same MAC address to 5 different port?
2. If yes, can ethernet switch "smart" enough to forward the packages to "active" ethernet port which is connected to notebook and the rest of four ports are inactive.
3. if no, any solution or any work around to achieve this requirement
I am unable to input the command "ip flow-cache timeout active 1" to my cisco 2960 and 4948 switches. But i am able to do so in my cisco 6500 series switch. Hence how do i enable netflow on both 2960 and 4948 devices?My 2960 and 4948 are L3 switches. What commands or additional hardware module are required.
I am having issue on my 3750G gig interface, it is not passing data more than 200M.Some how its giving me lots of input Pause on both sides,can some one explain if there is congesstion issue,do I need to enable flow control on both sides? [code]
On my Cisco SLM248G Switch the Back pressure and Flow control are currently disable.For the Flow control is it best to set it to enable or just Auto negotations and for the Back pressure is it ok the Enable it.This Cisco Switch has 3 servers and 15 laptop users connected to the ports.Will there be a draw back to enable these settings.
Struggling to find any documentation that states both "ip accounting & netflow" are supported on the new ME3600 switches. I have tried both a 12 and 15 release of software. Netflow produces no data what so ever, ip accounting only produces data (of the global network) when configured on my uplink (running MP-BGP network) unable to get specific data for user networks in seperate VRFs. Is this a case of the commands being there but not being supported?
I am really new to Cisco and having a hard time with my Cisco 2800 series.
I have two sites connected with each other Site A and Site B (Using the same Cisco 2800). Now site A can connect to site B on the Cisco and the internal network, but site B can only see the Cisco and not the internal network of site A. So all the traffic is coming in to site B but can't break out of site B. I have tried everything I can think of but again my knowledge of Cisco is not good at all.
I want to see net flow data.I have configured this command on the c6500.but I can to see data only below...How can I configration ip cache flow on the C6500? what is the problem?
int gi4/31 ip add x.x.x.x ip route-cache flow c6500# show ip cache flow Displaying software-switched flow entries on the MSFC in Module 5:
I'm receiving multicast traffic (400Mbps) on port 9/38 and sending it out on port gi9/48. I'm trying to achieve that traffic will stay within the card without using the switchfabric,
We have a pair of 6509 working in a VSS configuration (IOS 12.2(33)SX5). The 6509s connect to a pair of ASAs (7.2 code) running in an Active/Standby setup. These ASAs in turn connect to routers going to remote sites. I have configured Netflow on the following VLANS,
VLAN 10 - Servers Vlan VLAN 9 - Transit/ASA VLAN (connects ASAs to 6509s). All traffic originating from any VLAN on the 6509 crosses this VLAN in order to reach remote sites and vice versa
I configured the netflow source VLAN 11 although I am not collecing any netflow from it.Although I have been getting lots of Netflow info, I noticed that netflow for traffic originating from any user VLAN on the 6509s going to any remote site via TRANSIT/ASA VLAN(9) does not get reported, I even tested with 4 GB traffic but no result. Only reverse traffic (i.e. from remote site to user VLAN) is reported as it traverses the Transit VLAN (9).
I read somewhere that egress netflow is not supported in 6500, but isnt traffic originating from a user vlan to a remote site via the transit VLAN (9) considered ingress with respect to the transit VLAN (9)? I would like to know whether bidirectional Netflow is supported on 6500 VLANS. I have mimimum control on routers beyond the ASAs, and since these ASAs run 7.2 code netflow is not supported, and Monitoring this Transit Vlan gives me extremely useful info.
I do get netflow biderectional traffic from the Server Vlan 10, but I think it is correlated by the netflow collector from vlans 9 and 10. [code]
I have an 881 router here in house and am attempting to enable the gui interface on the router.
I have tried the steps to enable http but have not had any success. Below is the IOS Version and the portion of the show config that reflects the http allow:
ROM: System Bootstrap, Version 12.4(15r)XZ2, RELEASE SOFTWARE (fc1) Cisco 881 (MPC8300) processor (revision 0x100) with 249856K/12288K bytes of memory. Processor board ID FTX1249Y16Q
after installation of demo versions of 2900-SEC-TEMP & 2911-2921-SSLVPN-TEMP & rebooting the 2911 router I do not have access SSL commands.Show license indicates that 2900-SEC-TEMP & 2911-2921-SSL-TEMP licenses are active but NOT IN USE.
I have two WS-C2960-24TC-L Switch with Software Ver 12.2(25r)SEE6 with image c2960-lanbase-mz.122-35.SE5.bin and 12.2(25r)SEE1 with image c2960-lanbase-mz.122-25.SEE2.bin currently on it.
I want to enable SSH connections on the switches and believe I need to import the cryto image onto the switch. I would like to upgrade it to new version that can also support ssh connection but not sure which image to download from cisco. The switches are now live.
System image file is "flash:c2960-lanbase-mz.122-35.SE5/c2960-lanbase-mz.122-35.SE5.bin" cisco WS-C2960-24TC-L (PowerPC405) processor (revision H0) with 61440K/4088K
I have a pair of N7K's in vPC topology with some FEXs attached. I am looking into enabling Jumbo frame on the N7K as well as the FEX. I understand Jumbo frame is enabled globally by default.
My question is I have some interfaces in a port-channel that I need jumbo frame enabled. Do I enable it at the port-channel interface or at the physical interface ? and is the change disruptive to the network ? I am running NX-OS 6.0.2.
I have installed a EHWIC-4ESG card into my 2911 router running IOS Ver 15.1(4)M2. When I do a show diag, I can see the card, but I get the following line "Could not get card instance pa_bay=0 slot=0." Am I missing a step, do I have change something, is it not compatible (all that I have read, states that is)
One one of our Cisco 6509s I've globally enabled QoS and set a port to "trust cos". However when I look at the queueing for that interface, I notice that the receive queue thresholds have not changed to the default.
I'm kind of new to QoS so I'm not sure if I'm missing something.
We are using a Cisco 6509 running 12.2(33)SXI3 using the WS-X6724-SFP card. I thought I'd be seeing the default tail-drop thresholds, but instead I still see the defaults as if QoS were not enabled:
Queueing Mode In Rx direction: mode-cos Receive queues [type = 1q8t]: Queue Id Scheduling Num of thresholds
How to configure traffic flow between computers inside VLANs and a routed port? Here is the setup details:
1. Switch 3750-X 2. VLAN 100 - ( SVI IP address 192.168.100.1 /24) 3. VLAN 200 - ( SVI IP address 192.168.200.1 /24) 4. routed port gi1/0/48 (IP address 192.168.150.1 /24). Note: this port is directly connected to a firewall ASA 5520 port IP 192.168.150.100 /24
Ip routing is enabled on the switch and inter vlan traffic is flowing ok. I can ping the routed port gi1/0/48 from any computer connected in the VLAN 100 or 200. For example computer with IP 192.168.100.25 can ping the routed port 192.168.150.1. Switch can ping firewall port 192.168.150.100 and the 'sh ip route' command shows the network 192.168.150.0 /24 as directly connected network.
any computer in the two VLANs CANNOT ping firewall ASA port 192.168.150.100 Is it because inter VLAN routing does not work with a routed port on L3 switch? I looked up fallback bridging, but it is meant for non IP traffic.The goal is I am trying to set the ASA port as an internet gateway for VLANs.
I have recently split the voice vlan (10) from the data network (1), and am wondering why my catalysts and router do not require an interface Vlan10 statement. In the past I used OpenBSD boxes to do the routing, and I first needed to configure vlan 10 on the interface before I could get inter-vlan communication to work. With these Cisco devices it works, and I am wondering if it is because of VTP, for the fact that the ports maybe just pass all traffic, or is there some other explanation? Below is the setup, and firmware is up-to-date on all of the devices.
When I plug a phone into the POE SGE, the phone turns on, obtains an address on the proper subnet, and conversations are clear (whereas without the ip nat inside on the new subnet the calls had a lot of static). Possibly the reason that it works is because the phones properly create the tcp/ip packet, and it hops over the trunks and creates the states so that traffic routes back properly. I will install wireshark to see exactly what is going on, but is there a simple explanation that I am overlooking?
I have C2960S-48FPS-L and C2960S-24TS-S both of them are using C2960S-UNVERSALK9-M image with version 15.0(2)SE on both I run "mls qos"
and on 48FPS-L I run "mls qos map cos-dscp..."on 24TS-S I cannot run it. there is no such command. there is just "mls qos rewrite..." and "mls qos srr-queue..." variants.
I thought that one image give the same set of commands...?
I can not enable to rapid- protocol in catalyst 6513, does not support for it, only support pvst.
Someone how can i enable to rpvst? You know if is necessary to upgrade IOS, it has s72033_rp-ENTSERVICESK9_WAN-M - 12.2(18)SXF9 IOS. The cisco software Advisor could not localized the features fot this IOS.
why the QoS deployment causes ports on 2960 switches to drop packets although there is no bandwidth contension? (output bit/second of the interface)packet drops at threshold 1, queue 2 ( queue 3 in config)
We are using Catalyst 2960 switches and are experiencing issues with QoS. After the QoS, we experience a lot of packet drops and it make the network slow. It appears that the slow performance relates to the egress queuing of each port.
Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(50)SE5 WS-C2960-48TT-L
switch_06#show inter fa0/1 | in drops|queue|output input flow-control is off, output flow-control is unsupported Last input never, output 00:00:01, output hang never
I have a pair of Catalyst 3560 GB switches that are trunked with two of the standard ports, and that have trunk ports connecting to a failover pair of PIX 515e's. We're considering adding a pair of cluster database nodes and an iSCSI SAN, both of which would need a dedicated interconnect VLAN that I'd like to employ Jumbo frames on. I don't necessarily need the VLANs to traverse the firewall trunks since they're private interconnects, but I need each host to traverse the switch trunks.
Since it seems I can only enable Jumbo frames on the entire switch (current standard frame size is 1500 and jumbo is also 1500), when I enable it what kind of possible negative impact could this have on my trunked ports as well as my host connections? I've read mixed reviews of users with iSCSI SAN devices seeing terrible performance when enabling jumbo frames so I'm apprehensive about enabling them on an existing network.
I got some problem with enabling dhcp snooping on 4500 (cat4500e-lanbasek9-mz.122-54.SG.bin) the topology is as below: dhcp snooping enabled only on CORE (with interface trusted to dhcp server)the problem is that I put these 2 commands
ip dhcp snooping ip dhcp snooping vlan 1
but it is not enabled on any vlan
SW-CORE#sh ip dhcp snooping Switch DHCP snooping is enabled DHCP snooping is configured on following VLANs: none DHCP snooping is operational on following VLANs:
[Code]...
On B1 if I turn it on there is a "1" in the section " DHCP snooping is configured on following VLANs:" but on core no.As you can see I did put the trusted on the interface in the direction to the dhcp.First I thought it can be a problem with option 82, I've read a lot about the issues with that, but the problem would be explicable if the client did receive IP address, but it does.
I have 2 3550 12G switches that I use as core fiber switches. Switch 1 is the primary for 1/2 the V LANs and Switch 2 is the primary for the others using MST with 2 instances (I am not including the default 0 instance). I am using HSRP to provide redundancy. So far so good.
Recently a tenant in my building would like to use their own switch for data but still needs access to a V LAN on mine for voice. Again not a problem as I can configure a trunk port and give them what they need. My concern is that if they try to configure STP on their switch can they take down mine. Are there some preventions that I can put into place, such as root guard, that work with MST? What happens if they too set up MST can they kill mine?
Switch 1 is the root for 1/2 the v lans and Switch 2 is the backup root. The scenario is flipped for the other 1/2.
while i am configuring a port on switch .The switch reloads.After reload the show version says,System returned to ROM by bus error at PC 0x458F6C, address 0x0,show version from the effected switch is,Cisco IOS Software, C3750E Software (C3750E-UNIVERSALK9-M), Version 12.2(58)SE2, RELEASE SOFTWARE (fc1).
I am currently having an issue with connecting a Catalyst 2960-S switch to a Small Business SG300 switch. When I connect them they are unable to form a link. When I do a show spanning-tree it says the mst link is in dispute.
I read some papers about QoS. The thing is that I have to implement 30 switches with QoS to connect to a lot of Cisco IP phones. The switches are Cisco 2960S with code image "C2960S Software (C2960S-UNIVERSALK9-M), Version 12.2(55)SE3". Should I use autoQoS feature or manually configure them?. How should I treat uplinks between access switchs and core/distribution? I have a lot of doubts regarding queueing, because all the info I had read its for another model/image.
I'm looking at the WS-C2960S-48TD-L and have a question about the uplink ports. Is it possible to mix 10G on one uplink and 1G on the other? The datasheet says 2x10G SFP+, 2x1G SFP so I am thinking mixing is not possible.
