871W: Wi-fi to Wi-fi unreliable

I have a laptop on the wifi. It can connect to internet no problem. It can connect to almost every host on the wired LAN without problem.

There is an IPMI destination on the wired LAN which is sometimes accessible, sometimes not. (sometimes I can just start the GUI for server monitoring, and within a few minutes it will be able to connect, after which there is no problem - this never happens on the wired LAN portion). During failed attempts, the wi-fi device does get an ARP resolution for the IPMI destination.

Now howver, I try to ping or SSH to another wi-fi device (a phone) and it fails royally. I can telnet to a wired server from the laptop, and that server has no problem pinging or SSH to the phone.

So wi-fi to LAN seems to work. LAN to Wi-Fi seems to work. But Wi-fi to wi-fi seems to be a problem.

Is this common ? What should I look at in the config ?

While I am at it, for such a router, what would be the best way to run wireshark to scan all of the wi-fi traffic ? Can I do a port monitor on the BVI10 interface ?

Reply to
JF Mezei
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Bringing back an old (unsolved) thread.

I rebooted my Cisco 870 router today. And My iphone and laptop, both on wireless were able to talk to each other when I tried right away and both were able to contact the IPMI interface on the server (on ethernet).


I (now) know that this model's claim to support 5 VLANs is bogus becauise it has 4 vlans hardcoded which you can't remove (so you can only support 1 VLAN).

Is it possible that the 870 would have limits in the number of MAC addresses it can know about either gobally, or on a per interface basis ?

(The IPMI port is on the same physical ethernet cable as the server's main ethernet interface)

(IPMI is for system management and is active even when server is powered down).

The problem or two wireless devices not talking to each other seems sporadic, same with wireless devices not able to reach the IPMI. But from the wired etehernet I have no problem reaching any device, wired or not.

Reply to
JF Mezei


Cisco IOS Software, C870 Software (C870-ADVIPSERVICESK9-M), Version

12.4(15)T7, RELEASE SOFTWARE (fc3) Cisco 877W (MPC8272) processor (revision 0x200) with 118784K/12288K bytes of memory.

router#sh vlan-s

VLAN Name Status Ports

---- -------------------------------- ---------


1 default active Fa3 2 family active Fa0, Fa1, Fa2 3 test active 16 VLAN0016 active 1002 fddi-default act/unsup 1003 trcrf-default act/unsup 1004 fddinet-default act/unsup 1005 trbrf-default act/unsup

Nothing bogus there as far as I can see.

You do need a non-basic Feature Set. e.g. ADVIPSERVICES.

There are very probably hardware limits in the switch as there are in all switches. In the router bit, if bridging, the forwarding database and the ARP table will be in software and you will be limited only by system memory. How many MACs have you got?

I am not a wireless expert but I think you need to consider doing a survey for interference.

formatting link
be worth considering.

I would expect to see evidence of interference in the "show dot11 int" output. e.g. Retries, switching to low data rates, use of low data rates.

alt.internet.wireless has some good people and I have posted this there too.

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I have: router1#show version Cisco IOS Software, C870 Software (C870-ADVSECURITYK9-M), Version

12.4(15)T9, RELEASE SOFTWARE (fc5)

System image file is "flash:c870-advsecurityk9-mz.124-15.T9.bin"

And it won't let me create more than one VLAN.

My switch has 2 vlans defined (on top of the useless default ones) and is in vtp server mode.

Router doesn't accept vtp client and reverts to vtp transparent. (because it can't handle the 2 extra vlans).

I tried once to go to the cisco site to find the advanced software but it doesn't seem to want to let me download software for the 800 series routers. I may try again.

show mac on the router gives 12, but it lacks some. For instance it doesn't show the mac address of the BRAS router at the other end of a PPPoE interface.

Sort of strange that after rebooting, connectivity between wi-fi devices and between them and IPMI works fine.

Perhaps it may have limits on number of wi-fi devices. Since the reboot, it has only known about two. When I have friend over, perhaps the problem will re-occur.

Reply to
JF Mezei

#sh ver Cisco IOS Software, C870 Software (C870-ADVIPSERVICESK9-M), Version 12.4(15)T11, RELEASE SOFTWARE (fc2)

#sh vlan-switch

VLAN Name Status Ports

---- -------------------------------- --------- -------------------------------

1 default active Fa1, Fa2 2 SDSL active Fa3 10 Telefonie active 1002 fddi-default act/unsup 1003 token-ring-default act/unsup 1004 fddinet-default act/unsup 1005 trnet-default act/unsup

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2

---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------

1 enet 100001 1500 - - - - - 1002 1003 2 enet 100002 1500 - - - - - 0 0 10 enet 100010 1500 - - - - - 0 0 1002 fddi 101002 1500 - - - - - 1 1003 1003 tr 101003 1500 1005 0 - - srb 1 1002 1004 fdnet 101004 1500 - - 1 ibm - 0 0 1005 trnet 101005 1500 - - 1 ibm - 0 0

From running-conf: interface FastEthernet0 switchport trunk allowed vlan 1,3-4094 switchport mode trunk ! interface FastEthernet1 ! interface FastEthernet2 ! interface FastEthernet3 switchport access vlan 2 !

#sh vtp status VTP Version : 2 Configuration Revision : 3 Maximum VLANs supported locally : 8 Number of existing VLANs : 7

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router1#show vtp status VTP Version : 2 Configuration Revision : 0 Maximum VLANs supported locally : 6 Number of existing VLANs : 6

So with the default software version, you have 5 default VLANs which you can't delete (vlan 1 and 4 strange ones), which leaves just 1 you can define.

Since I have the "crippled" version, I have to wonder what other artificial restrictions exist on the unit. When I purchased it, I figured 6 VLANS was plenty. Didn't know 6 vlans really meant just 1.

Reply to
JF Mezei

I don't know why your model only allows 6 while mine allows 8. I use 3 vlans and I would not have enough with 6 allowed either.

I agree with you that it sucks that you cannot delete those 4 fixed vlans. I don't use token ring and I never will. I don't need a token ring vlan.

Reply to

It is, always has been, and always will be the Cisco way to sell routers or whatever with a single set of marketing blurb then to have different versions of the software for different costs that offer various subsets of the functionality.

It's no different for cars or Microsoft Windows or any other complex product.

Maybe they should do it some other way but I bet that won't happen any time soon. You need to check the features you need against the documentation before purchase. If you can't understand the documentation then you need to hire someone who does.

My view is that the products are intended to be specified by experienced professionals just as steel beams for buildings might be. Complaining to a supplier of construction materials that you didn't know what you were doing when you ordered a hundred tons of steelwork but got the wrong stuff will I would guess cut no ice at all. It is the same here. Don't be fooled that an 800 series router only costs a few hundred pounds, as I think you know it has the same software features as a router that costs hundreds or thousands of times as much. The documentation for that $300 router extends to thousands and thousands of pages (I have no estimate now but 10 years ago when you could still get paper manuals the set looked like about 10 telephone directories and there are many times the number of features now).

Good luck:)

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