SmallNetBuilder Forums
Go Back   SmallNetBuilder Forums > LAN & WAN > Switches, NICs and cabling

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 07-30-2010, 04:30 PM
Jeroen1000 Jeroen1000 is offline
Member
 
Join Date: Dec 2009
Posts: 59
Thanks: 0
Thanked 0 Times in 0 Posts
Jeroen1000 is just starting out
Default VLAN: Can't access switch anymore

I'm stumped about getting this to work so I hope someone can lend a hand.

I don't even know how to begin explaining but I'll try. I have read the VLAN articles but I still can't figure this out.

My switch, a Cisco SLM2008, has become unreachable. No ping, no webinterface. Its management "interface" is in VLAN 1.

The setting that caused this is, is called "acceptable frame type". I set this to "tagged only". Two other strange options I have left unchecked:
Enable Tx Force Untag (was unchecked by default)
Enable Ingress Filter (was checked by default)

My network layout:

Switch port 1 (VLAN 1, VLAN2) ------- > Draytek router port 3 (VLAN 1)

Draytek router port 2 (VLAN 1) ------> regular "dumb" switch port 1

My desktop is conntected to the "dumb" switch.

So, I'm thinking the switch rejects my traffic because the traffic comming from my desktop is untagged. However, port 2 of the Draytek is in VLAN 1. Sinde my desktop is conntected to a switch which is conntected to port 2, I would have thought the Draytek would tag the frame?

Anyway, I'm just speculating and help is more than welcome!

Last edited by Jeroen1000; 07-30-2010 at 04:33 PM.
Reply With Quote
  #2  
Old 07-30-2010, 08:36 PM
Jeroen1000 Jeroen1000 is offline
Member
 
Join Date: Dec 2009
Posts: 59
Thanks: 0
Thanked 0 Times in 0 Posts
Jeroen1000 is just starting out
Default

Alright, I've come up with a theory. I just need a way to verify it.

I think the Draytek does not understand what a trunk port is. I believe it UNTAGS the frame before sending it to the Cisco switch. And since the trunk on the Cisco side will not accept untagged frames, I have a total lockout.

Simplest way to 'unlock' this situation (apart from resetting the switch) would be to connect the Draytek to another port on the Cisco which still accepts untagged frames. But unfortunately, I can't do that. The Cisco is POE powered and it can only draw its power from the special POE port.

A laptop would come very in handy now!

Does anyone know of a way to confirm my suspicions? Certainly I would like to regain access, but then I would still need to find out why this isn't working out.
Reply With Quote
  #3  
Old 07-31-2010, 09:45 AM
Jeroen1000 Jeroen1000 is offline
Member
 
Join Date: Dec 2009
Posts: 59
Thanks: 0
Thanked 0 Times in 0 Posts
Jeroen1000 is just starting out
Default

small update: after reviewing more Draytek documentation, I now know this router is unable to support a trunk. It can be reached via SSH so I assume I can create a trunk but I don't know yet how to. I've asked Draytek whether they want to consider helping me on this.
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


All times are GMT -4. The time now is 12:07 PM.


Top 10 Stats
Top Posters* Top Thanked
RMerlin  414
stevech  139
KGB7  123
azazel1024  118
sfx2000  97
sinshiva  95
Kel-L  93
hggomes  83
fistv  78
john9527  69
RMerlin  5586
stevech  329
ryzhov_al  265
TeHashX  217
RogerSC  189
L&LD  189
sinshiva  143
joegreat  127
jlake  122
sfx2000  120
Most Viewed Threads* Hottest Threads*
Old Asuswrt-Merli...  76742
Old Asuswrt-Merli...  39751
Old [Fork]...  16367
Old Asus locking...  9916
Old ASUS...  7919
Old Incoming...  7754
Old [Fork]...  4418
Old Share What...  3578
Old Asuswrt-Merli...  2889
Old Ac68u Latest...  2123
Old Asuswrt-Merli...  393
Old Asuswrt-Merli...  189
Old Asus locking...  125
Old [Fork]...  123
Old Connection...  51
Old [HOW TO]...  50
Old ASUS...  49
Old Incoming...  44
Old [Fork]...  42
Old 376.44 -...  40


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
© 2006-2014 Pudai LLC All Rights Reserved.