Arp aging time on router and mac address aging time on switches set close t

Hi,
appreciate some advice on the following:
what is the benefit of setting arp aging time on router and mac address aging time on switches close to each other?
Thanks,
Christina

Hi,
based on the below output, do you think implementing it will benefit? Thanks.
C2950#sh int fa0/43
FastEthernet0/43 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 000d.5e11.4e2b (bia 000d.5e11.4e2b)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000 usec,
reliability 255/255, txload 7/255, rxload 2/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s
input flow-control is off, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:00, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 933000 bits/sec, 149 packets/sec
5 minute output rate 2981000 bits/sec, 263 packets/sec
2819781393 packets input, 3782332886 bytes, 0 no buffer
Received 266693 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
4015025747 packets output, 2328228393 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
C2950#

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SG300 inter-VLAN routing and MAC address changes in incoming packets

Hello
I have SG300-20 working in Layer3 mode
VLAN1 is not used
Internet gateway is in VLAN211
Clients are in other VLANs
Switch is default gateway for clients and itself has internet gateway as default route.
MAC address of switch is XX:XX:XX:XX:XX:63
When client sends trafic to Internet destination MAC address in outgoing packets is XX:XX:XX:XX:XX:63
But in incoming packets source MAC address is XX:XX:XX:XX:XX:69
Why does it change? And how can I setup switch to use only XX:XX:XX:XX:XX:63 MAC address?

Hi Robert,
I'd like to pick up this old thread because we have a huge problem with the behavior of the SG300 router/switch regarding the "spoofed" MAC source addresses. We have connected this switch to another router which has some special routing capabilities. It routes certain IP packets directly to MAC addresses which it learned from snooping on special traffic.
When connected to a SG300 router with an Ethernet base address of XX:XX:XX:XX:XX:48 we receive packets with Ethernet source addresses like e. g. XX:XX:XX:XX:XX:49 or XX:XX:XX:XX:XX:4D (depending on which hardware port they came from). Our special router "learns" these MAC addresses and tries to send associated outgoing packets directly to these addresses using e. g. XX:XX:XX:XX:XX:49 as the MAC destination address.
Our problem is that the SG300 does not forward the packet if the MAC destination address is not equal to the switch's Ethernet base address (XX:XX:XX:XX:XX:48 in our case). This renders the SG300 series useless for our systems.
Is there new firmware available which fixes this problem for us? We don't care which MAC source address the SG300 uses in incoming packets we receive, but we expect that the SG300 handles packets correctly for outgoing packets we send with this MAC address as the destination address.
Thanks,
Chris

3750 mac-address-aging timer

Hi,
i'm trying to change mac-address timers but having problems, i.e the change Im trying to change mac-address-aging timers but having problems, i.e. the change only applies to existing active vlans. if i add new vlan after changing mac-address-aging timer it will have default value 300. Is this way it works or Im missing something?
3750-sw-1(config)#mac-ad aging-time 1300
3750-sw-1#sh mac-ad ag
Vlan Aging Time
10 1300
20 1300
30 1300
3750-sw-1#! Now adding a new vlan
3750-sw-1#conf t
3750-sw-1(config)#vlan 40
3750-sw-1 (config-vlan
3750-sw-1#sh mac-ad ag
Vlan Aging Time
10 1300
20 1300
30 1300
40 300
New vlan 40 has default value????

Just checked the command reference. In the usage guidelines it states:
Usage Guidelines
If hosts do not send continuously, increase the aging time to record the dynamic entries for a longer time. Increasing the time can reduce the possibility of flooding when the hosts send again.
If you do not specify a specific VLAN, this command sets the aging time for all VLANs.
The last sentence is relevant to your question. The command may also be issued on a particular vlan.
New vlans are created after setting this parameter globally will hence be using the default values.
The key issue to check if this is a bug or not is to check whether the global command is reflected in the config. If it was, I would call the issue a bug.
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Regards,
Leo

Dot1x disable mac-address aging

Hi, all!
I have configured dot1x on 3560 switches on my network. Switches have been configured to send MAC notification traps. I have set mac address-table aging time to 1800 sec. but only 802.1x not enabled switch send trap periodically. It seem dot1x technilogy disable mac-address aging process.
Can anybody explain it.

You can control mac-address learning for a VLAN by using this switchport command on a trunk.
Router(config-if)# switchport port-security maximum 3 vlan 102
Or simply use this to allow only a certain number of mac's per access port.
Router(config-if)# switchport port-security maximum 1
Here is the command reference.
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122sr/cr/srir_r/ir_s4sr.htm#wp1015189
PS: you cannot totally stop mac learning as the valid values are from 1-4097 so you cant set it to zero and i believe you dont want to as well , since you have a layer2/3 environment.
HTH-Cheers,
Swaroop

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I have had my iTouch for about a week and it connected to my wireless network for the first three days flawlessly. Since that time, it will only connect sporadically and I have noticed that when it doesn't connect, it is because the router and DNS addresses have disappeared in the wireless window in Settings. I can get them back occasionally by renewing lease in this window, but more often than not, renewing lease does not reestablish these addresses.
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Message was edited by: tritium11

Is your router broadcasting its SSID? If not, try enabling that because the Touch often has a hard time remembering a network if it is hidden. Hiding your SSID is very minimal security, so there's really no point to hiding it.

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Hi there,
How to change mac address on time capsule?

There are routers that allow you to create/clone a mac address to whatever you like. Since many companies use the mac address to 'register' a unit connected to it's system, you usually just have to let them know you've changed your router and they will reset your system to accept connections from the new device.

Just moved to new home, updated router and new system with Time Warner and now we cannot get the appl

just moved to new home, updated router and new system with Time Warner and now we cannot get the apple any ideas?

Castle15 wrote:
just moved to new home, updated router and new system with Time Warner and now we cannot get the apple any ideas?
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Hi!
Is it possible that we recibe IP address and Mac address Client at the same time in ISE ?
The wlc permits choose radius Call station ip type MAC or IP, but not both.
Thanks you,

If you are using dot1x then no, the mac address is sent since the client does not receive an ip address till authetication succeeds.
Sent from Cisco Technical Support Android App

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Hi all,
I have a problem with 4503 switch
I have 7 highend servers in my lan i.e 5hp and 2dell servers.
Each server has 4 network interface cards(1g). so 7*4=28 ports.
I have create vlan 70, ip add is 10.70.70.1
I have assign ip address to servers like
first server         10.70.70.2, 10.70.70.12,
Second server   10.70.70.3, 10.70.70.13,
Third server        10.70.70.4, 10.70.70.14,
fourth Server       10.70.70.5, 10.70.70.15, 10.70.70.25, 10.70.70.35
fifth server           10.70.70.6, 10.70.70.16, 10.70.70.26, 10.70.70.36
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                                            i can't able to ping 10.70.70.2- macid 60eb.69d2.a2ab
second, fourth, fifth, sixth, and seventh continiously pinging successfully.
for example in fourth server i can able to ping 10.70.70.5 macid -b499.bafe.9c98
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Hi,
I Think you need to do Teaming on the servers.
++ configure etherchannel between switch and the server.
configuring etherchannel b/w 4503 and server:
================================
http://www.cisco.com/en/US/tech/tk389/tk213/technologies_configuration_example09186a008089a821.shtml
Sample NIC Teaming - HP NICs with Cisco Switches (EtherChannel) :
==============================================
http://support.citrix.com/article/CTX434260
There are several NIC teaming technologies available today from switch vendors. Cisco uses the term “EtherChannel.” Various switch vendors use various terms, and these may or may not provide the same exact functionality. Use of EtherChannel technology requires support from the server hardware vendor, NIC vendor, and Layer-2 switch vendor.
Hope this helps
Cheers
Somu
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How I can lock my Time Capsule on specific MAC addresses?

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Experts,
I’ve recently installed a pair of 5525X’s in transparent mode to protect some internal segments. In reading about transparent mode I thought I read that the ASA will “proxy” the connection when going from the Layer 3 side (North) to the actual physical South side host. For an “Outside/North” host (vlan 700) to talk to an “Inside/South) host (vlan 800) the ASA will pass it’s mac-address to the outside host (or gateway) as the destination to send the packet. Prior to building this infrastructure I thought I would see all ARP entries on the Layer 3 (North) side to have a mac-address of the interface of the ASA for all protected hosts. I do not see that on the SVI interface but do see the real mac-address of the “South” side protected machine. When looking on a protected machine I do see the default-gateway ARP entry to be the actual mac-address of the SVI on the switch and not the mac-address of the ASA which I thought would be the case as well. Everything is working as advertised (or so I think) as removing or adding ACL’s does limit or allow traffic so it appears to be working. I’m just checking that my initial assumption of the mac-address of the ASA being on every ARP entry was/is incorrect. From what I can tell the ASA passes the mac-address's from each side of the bridge-group to the other.
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http://support.apple.com/kb/TS2986

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http://www.cisco.com/en/US/products/sw/secursw/ps2086/products_configuration_example09186a00807917aa.shtml
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As a simplest possible solution, you can use the system command
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Hello Everyone,
I am migrating my DHCP services from an old SUN server to an OES Linux server. In the old SUN files, my client identifier and mac addresses have a leading pair. So if my mac address is 00:30:C1:57:44:09, it is entered in the SUN files like this: 01:00:30:C1:57:44:09. My question is, do I need to enter that extra pair in my host records for OES Linux DHCP? If I do or don't, does it matter?
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On 21/06/2010 19:46, toneyc wrote:
> I am migrating my DHCP services from an old SUN server to an OES Linux
> server. In the old SUN files, my client identifier and mac addresses
> have a leading pair. So if my mac address is 00:30:C1:57:44:09, it is
> entered in the SUN files like this: 01:00:30:C1:57:44:09. My question
> is, do I need to enter that extra pair in my host records for OES Linux
> DHCP? If I do or don't, does it matter?
Whilst I've seen this with NetWare-based DHCP the DHCP on OES Linux uses
different objects and is provided by ISC DHCP which does not have this -
my DHCP hosts are configured just with MAC address.
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01:23:45:67:89:ab" (where 01:23:45:67:89:ab is MAC address).
> The reason I'm asking is that many of my older printers and even some
> of the newer ones are not picking up an address from the new DHCP server
> when the old one expires.
Just printers or other types of devices too?
If printers, particularly HP ones, check that they're set to pick up IP
details via DHCP and not BOOTP. Yes should still work but we've seen
problems here.
HTH.
Simon
Novell Knowledge Partner (NKP)
Do you work with Novell technologies at a university, college or school?
If so, your campus could benefit from joining the Novell Technology
Transfer Partners (TTP) group. See www.novell.com/ttp for more details.

Arp aging time on router and mac address aging time on switches set close t

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