Cisco Switching/Routing :: Auto-QoS On Catalyst 3750 LAN Switches?
Aug 12, 2012
why the AutoQoS macro does not implement "priority-queue out" when configured on the 3750 platform running certain versions of software. The only other platform I have experience with AutoQos is on the 4500 and it enables priority queuing as expected. So what's up with autoqos on the 3750 on version 12.2(35)SE5?
When it comes to configuring QoS on campus user/phone access ports there are some important settings that can and should be considered but one can argue that enabling the priority queue is the single most impactful or important command. So I was very surprised and concerned when I didn't see priority-queue out. Cisco describes AutoQoS as a simple, quick way of deploying QoS on the LAN and it precludes you from having to learn all of the differences between hardware platforms. But is it true that this tool produces an incomplete config solution? Let me know if I am missing something.
Here is an example of what AutoQoS produces when applied to a 4507 with WS-X4648-RJ45V+E:(other interface commands are left out for simplicity)
interface GigabitEthernet5/25description XYZ
switchport mode accessauto qos voip cisco-phoneqos trust device cisco-phoneservice-policy input AutoQos-VoIP-Input-Cos-Policyservice-policy output AutoQos-VoIP-Output-Policy
policy-map AutoQos-VoIP-Output-Policy
class AutoQos-VoIP-Bearer-QosGroup
set dscp ef
[code]......
Here is an example of what AutoQoS produces when applied to a 3750 running version 12.2.(35)SE5: (no priority-queue out)
We have a couple of Cisco switches and connected a (Windows 7) laptop to one of them and it gets its IP address from a DHCP server.I can now ping the IP from all of the switches, no problem, also not when I log on to the core switch in the same VLAN as both notebooks. But from my (Windows 7) laptop, which is in the same VLAN as the target laptop, I cannot ping it.
I checked, default gateway is good on both sides, as are DNS servers.
what is the difference between Cisco Nexus switches and the usual catalyst 3750 switches.I do understand the operating system in both these are different.
When will we suggest using Cisco nexus instead of usual Cisco switches? Also what interface does Cisco nexus like 5548 come with , is it both copper and fiber?
I have a 3750 that when a client computer shuts down the switch will not discover it on start-up unless I bounce the switch. Pretty dependable product so,.... did I miss something in my config? Switch is GBIC'd for Fiber?
I have an issue where I'm seeing output discards on pretty much all my ports configured for QoS. The switches are cisco WS-C3750V2-48PS running 12.2(50)SE1. There are four switches stacked using stack cables. The QoS implemeted was auto-qos with no modifications to the standard config. All ports are in queue-set 1. The phones connected are Cisco 7942's. Already did the standard check for speed duplex mismatch, crc's, runts, giants, etc...No discards before the QoS was applied. No bug ID's I could find regarding these switches and this IOS version. The one thing noticed is that 99% of all the drops are from queue's 2 and 4 or 1 and 3 doing the below command.
**I've limited the cut and paste as to not clutter the discussion until someone requests something else**
show platform port-asic stats drop Port 18 TxQueue Drop Statistics Queue 0 Weight 0 Frames 0 Weight 1 Frames 0 [Code]....
We have a switch that, when configuring auto qos on and edge port facing video equipment, the upstream port channel drops. I was wondering if no auto qos would have to be configured on the member ports of the port channel prior to enabling auto qos on any other ports.
have 3 Catalyst 3750 in same stack, the IOS version is 12.2(53)SE2. Today we can not telnet/ssh to this switch, but ping is ok, and switch function is ok. I try to access the console port, it show "low on memory, try again later". After I reboot the master switch in the stack, the master switch change to another switch, then I can telnet/ssh to this switch. I check the Ciscoworks server syslog report, there are many MAC address flapping error message, and I beleive the MAC address flapping occured before several weeks. ( the G2/0/15 & G3/0/15 is connect to a VMware ESX server and the EtherChannel config mismatch with this Catalyst 3750 switch ) How to mention the root cause of the "low on memory" problem and what is the abnormal memory usage ( free memory percentage below ?% )?
my Catalyst 3750 switch. Following a power cut the switch no longer boots up. The SYST light flashed green but no POST checks are made. I cannot see any boot messages from the console port either. The switch was on a UPS but some thing may have damaged the switch.
There is a requirement to configure tacacs and radius on catalyst 3750X (version 15.0) where two vrf exist.Is therer a solution to configure "tacacs-server,host x.x.x.x vrf yyy" ?? I know it is possible to configure under the "aaa group server radius xxx" the command "ip vrf forwarding yyy".Is there anything else for the tacacs-server and radius-server command?
I have a network with a Catalyst 3750 as the main switch and then some Catalyst 2960 switches that are plugged in to that. I have a server running windows server 2008 with a couple of virtual machines running in Hyper-V. I created 4 VLANS listed below and gave the 3750 the following IP Address.I would like the 3750 to only be configurable from VLAN 40 but currently every VLAN can connect to it, I noticed in the standard web page settings there was a setting for "Management VLAN" but it was set to 1 and would not let me change it, I kinda assumed that was for the management port in the back.-Now the tricky part, I was trying to set up routing between the VLANs and so far I have only been able to get a sort of "all or nothing" routing to work. I can turn IP routing on and add two or more VLANs to the routing and it works fine. But what I was hoping to do is create a couple of "junction vlans" that would only route to one or two other vlans. For instance, I wanted to create a VLAN 100 that routed to VLAN 20 and 30 but nothing else. I also want to route VLAN 1 just to VLAN 30, and so on. I am able to do each one of the cases but only one, it seems like the switch only supports one "routing table" am I missing something or is this just a limitation of the switch?
I have a network with several catalyst 2960 switches and one catalyst 3750. I have created two VLAN and set up the proper routing and everything is working fine there. I have a client/server application that used multicast in the initial start up for the client to determine available servers, the issue is one of my clients is on a different VLAN then the server. I am able to route the multicast using MVR as long as both the server and the client are plugged into the 3750 by creating a static route, making the server a source port and the client a receive port. Unfortunately I need the client and the server plugged in to different 2960s. My question is how do I establish multicast routing between the two and perferably do it dynamically (always route multicast traffic from one VLAN to another).
I have been looking into this for a while and I can't seem to figure out why my 2nd vlan is not able to connect properly to the net.
My switch has 12 ports where my devices connects directly, they are all on Vlan 1 and they all work perfectly. on Port 12 I have a dlink router that is connected to a cable modem. the dlink router has an Ip address of 192.168.0.20
I created a second vlan (vlan2) and enabled dhcp relay on it. then I assigned port 9 on the switch to (vlan2)my laptop which is connected to port 9 seems to get an ip address fine and able to ping only some devices on my network (vlan1) and is not able to go out to the internet. I think it has to do with the routes. [code]
I have been looking into this for a while and I can't seem to figure out why my 2nd vlan is not able to connect properly to the net. My switch has 12 ports where my devices connects directly, they are all on Vlan 1 and they all work perfectly. on Port 12 I have a dlink router that is connected to a cable modem. the dlink router has an Ip address of 192.168.0.20,I created a second vlan (vlan2) and enabled dhcp relay on it. then I assigned port 9 on the switch to (vlan2),my laptop which is connected to port 9 seems to get an ip address fine and able to ping only some devices on my network (vlan1) and is not able to,go out to the internet.
I was browsing the Software Adviser on Cisco's website to look for a suitable IOS image, for a 3750. The system displayed a couple of suggested IOSes. there was no mention of IOS 15.0SE version.Could the Software Advisor be not up to date with the current Catalyst IOS releases?
I have CISCO catalyst with VLANs (VLAN ID 33, 36, 40-53) configured. I need to configure port mirroring in Switch 3750 for NAC (Network Access Control). I need to Monitor all the VLANs. Here is the SPAN configuration of switch: [code] Monitor session 1 source vlan 33 , 36 , 40 – 53.Monitor Session 1 destination interface fa 1/0/8 (here I am not able to set encapsulation dot1q ) because the error occurred saying %one or more dest port do not support the encapsulation%.
I have customer who has as Core Switch one Cisco Catalyst 3750 with the IOS c3750-ipbase-mz.122-35.SE5.I know that this image support DHCP Server configuration, but I like to implementate new vlans (approx 15) and I want to know if this switch support 15 DHCP Servers.
How to setup a port channel between a SG200 and 3750 and am having problems.
What do I need to do on the SG200 I have added the port into the lag but the port will not come up.
I spent half a day messing arround with the web interface and I am unable to get the port to come up.
The Cisco 3750 is a standard port channel config which I have setup maytime before. channel-group 1 mode active channel- protocl lacp Switchport mode trunk
I am working in an environment where i have to use more etherchannels, any way that how many etherchannels could we create on Cisco Switch 3750 e. do they can utilize high process resources of CPU.
if I read the Datasheet of Catalyst 3750X-Series-Switches it is possible to connect a new X-Switch to an existing and old Catalyst 3750-Series Stack.What kind of requirements are needed? Only same IOS-Version in the hole Stack and if possible same Feature-Set? .... like in a normal NOT mixed Stack?
I have 3 VLANs here that need to be on the same network segment. They are going to be used by our Wi-Fi network (with Aironet APs), bound to 3 different SSIDs (as Aironet APs doesnt allow multiple SSID per VLAN), each one with a different authentication method and server.Is there a way to bridge those VLANs together with a Catalyst 3750 switch? I tryed configuring an IP address on one of the VLAN interfaces, then configuring a bridge with the vlan-bridge protocol (Catalyst 3750 doesnt have the "ieee" bridge protocol type) and put all 3 VLAN interfaces on the same bridge-group, but it didnt work (even with "bridge x route ip").I also tryed configuring IRB bridging, with the 3 VLAN interfaces on the same bridge-group and an IP address on the BVI interface (the way I used to do with old 2600 routers). Same result.(actually, I didint test to see if the interfaces are actually being "bridged", but I see neither of them can reach the router)
I am trying to use a SF302-08P switch to connect a conference phone (Cisco 7937) to my infrastructure. I connected the G2 port on the SF302 to a Gig copper port on the Catalyst. I configured both ports as trunked ports and port e1 on the SF302 as an access port for the phone. VLAN 1 is the default VLAN and VLAN 10 for voice. However, the phone does not connect to the Call Manager. I have changed the configurations on the G2 trunked port and the ethernet port (trunked ports, general ports, tagged and untagged). I have also changed the configuration on the Ethernet port (general, access, trunk, set it on the default VLAN, in the voice VLAN, etc.) The SF302 connects to the Catalyst, and PCs connect OK.
Our servers are hosted at the Main site, site office A access to the Main site for Internet and servers. We are thinking NextG to take over when the link between sites goes down.
To start with, what is the configuration for 3750 at Site A and the Main site:
1) Trunking for both switches
2) Routing
3) the automatic failover configuration for the switch at Site A.
I have the wrong code on the device. I can get to the switch: prompt. The manual say to connect a PC to the management port. But it does not come up. x modem does not seem to work. I found some commands :
Examples : This example shows how to clear the Ethernet management port statistics: switch: mgmt_clr
In my ongoing project i need to monitor cisco 3750-X port status (uplink/downlink) i.e. whenever there is some problem at a specific port. I need to monitor it through an OPC server and right now what i am doing is as follows: i am using Kepserver and i have added SNMP driver in it for that purpose i am not a networking expert but what i have learnt till now is that SNMP agent (that resides in switch) delivers the status of MIBs to SNMP manager ( which in my case is kepserver (opc server)) for the above purpose i am adding IF-MIB to monitor OID 1.3.6.1.2.1.2.2.1.8 (which shows port statuses) but when i add that in OPC server then it indicated that this OID is not available in the Switch ( it might be disabled) so i need to ask if there is any way to enable OID's in a switch,
I want to run rolling-stack upgrades on several stacks containing Catalyst 3750X-switches. I have done as follows: Configured the redundant uplinks as active and stand-by.Started to upgrade by using archive download-sw /rolling-stack-upgrade /overwrite /reload The upgrade starts as expected BUT switch number 2 in the stack is reloaded BEFORE switch 1 is finnished, the result is of course downtime for the stack. The documentation says something about the command "boot time", but what is this command doing? The default seems to be 7 minutes, it this parameter the time the upgrade-process waits before booting the next switch in the stack? I would expect that switch number 2 is reloaded when switch 1 is up again after reload, and not after an absolute number of minutes, is the rolling-stack-upgrade not working this way ?
I am running the latest version of 12.2(55)SE6 on the catalyst and I am looking for this command "lacp rate fast" but it is not there:
lab-c3750#conf t Enter configuration commands, one per line. End with CNTL/Z. lab-c3750(config)#interface g1/0/5 lab-c3750(config-if)#lacp ? port-priority LACP priority on this interface lab-c3750(config-if)#lacp
According to this link, it is supposed to work: [URL]Am I missing something?
I have installed a Catalyst 2960-S and a 3750-X-12S and I am trying to setup a VLAN 51 for some VoIP phones. I have added the VLAN as an interface on both switches, but the 3750 is not showing VLAN 51 as active when i do a show vlan. Also, it omitts showing Gi1/0/1 & Gi1/0/3 which are uplinks to 2960-S switches plugged in and working on VLAN1.
Catalyst3750SFP#show vlan VLAN Name Status Ports ---- -------------------------------- --------- ------------------------------- 1 default active Gi1/0/2, Gi1/0/4, Gi1/0/5
I have got a new 48port Cisco catalyst 4948 switch, which I configured as a VTP client and connected to Cisco 3750 which is a VTP Server (this switch is on production network). I connected port g1/0/48 from 3750 to port g1/48 on 4948 through a straight cable and made both ports as trunk port (I also tried through cross cable). The problem is these two switches are not detecting. For testing I connected a PC directly to one of the port on 4948 (making that a switch port) still the LED on switch didn’t glow up. Is there any special command needs to be run on 4948 switches to activate its physical ports?
