os:ios:vlan.dat
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Table of Contents
vlan.dat
under construction…
Structure
Offset | Bytes | Type | IOS Name | Values | Notes |
---|---|---|---|---|---|
000 | 4 | string | - | BADB10 | Magic Number? |
004 | 4 | int | VTP Version | 2, 3 | - |
008 | 1 | char | VTP Operating Mode ID | 1 (client), 2 (server), 3 (transparent) | - |
009 | 1 | char | - | VTP Domain Name Length | |
00a | 32 | string | VTP Domain Name | - | |
02b | 6 | ? | Configuration Revision | - | - |
030 | 4 | int | Local updater ID | IP address | |
034 | 4 | int | Last update on | vlan interface with lowest number | |
038 | 12 | string | Configuration last modified by | yymmddhhmmss | |
044 | 8 | bytes | MD5 digest | - | |
04c | 8 | ? | ? | - | |
054 | 1 | char | - | VTP Password Length | |
055 | 64 | string | VTP Password | - | |
095 | 3 | int | Number of existing VLANs | this may be 2 bytes not 3. There should be enough VLANs with two bytes: 2^(8*2)-1 = 65535. |
|
098 | 8 | ? | ? | - | |
Repeats for each VLAN 1) | |||||
0a0 | 1 | char | Name Length | ||
0a1 | 32 | string | Name | ||
0c1 | 2 | short | Type | 1 (enet), 2 (fddi), 3 (trcrf), 4 (fdnet), 5 (trbrf) | may is just a char, not short. would be enough, but no idea what the first byte could be |
0c3 | 1 | char | State | 1 (active), 2 (suspended) | |
0c4 | 2 | short | MTU | 576-18190 | |
0c6 | 2 | short | ID | 1 to 4094 | Extended-range VLANs (VLAN IDs 1006 to 4094) are only saved in the VLAN database in VTP version 3. |
0c8 | 4 | int | SAID | 1 to 4294967294 | |
0d8 | 2 | short | Ring Number | 1-4095 | FDDI or Token Ring |
? | 1 | char | Bridge Number | 0-15 | FDDI Net or Token Ring Net |
? | 1 | char | STP Type | 0 (none), 1 (ieee), 2 (ibm) | FDDI Net or Token Ring |
? | 2 | short | Parent VLAN | 0-1005 | FDDI or Token Ring |
? | 8 | ? | ? | ||
? | 1 | char | Remote SPAN | 0 (disabled), 1 (enabled) | |
? | 1 | char | ? | ||
Following Stuff is yet unknown | |||||
… | 96 | ? | ? | ? | ? |
I got most of the information from Chris Welsh (decoding vlan.dat). Thank you.
Notes About Missing Parts
VLAN
1)
- Remote SPAN (enabled, disabled) ⇒ char (1)
- VLAN state (active, suspend) ⇒ char (1)
- Translational bridge 1 (0 to 1005) ⇒ short (2)
- Translational bridge 2 (0 to 1005) ⇒ short (2)
or: 2)
- Parent (Parent VLAN, if one exists.)
- RingNo (Ring number for the VLAN, if applicable.)
- BridgeNo (Bridge number for the VLAN, if applicable.)
- Stp (Spanning-Tree Protocol type used on the VLAN.)
- BrdgMode (Bridging mode for this VLAN—Possible values are source-route bridging (SRB) and source-route transparent bridging (SRT); the default is SRB.)
- Trans1 (see below)
- Trans2 (see below)
trans1 & trans2:
Types of translational bridges that the VLAN in the VLAN column is configured to translate to. Translational bridge VLANs must be a VLAN media type different from the affected VLAN; if two VLANs are specified, each one must be a different type.
Common VLAN types include Ethernet (enet), FDDI (fdnet), and Token Ring (tnet). The numbers in the Trans1 and Trans2 columns refer to the VLAN ID numbers of the translational bridge VLANs.
Note The term VLAN translation is also used in Cisco configuration guides for mapping specific VLANs in a given trunk to another VLAN that is of the same media type. In this context the term VLAN translation refers to a form of VLAN mapping that is using the term VLAN translation to describe it.
– http://www.cisco.com/c/en/us/td/docs/ios/lanswitch/command/reference/lsw_book/lsw_s2.html
it looks like this is Token Ring information… so, rather 2) than 1). http://www.cisco.com/c/en/us/td/docs/ios/12_2/ibm/configuration/guide/fibm_c/bcftrrsm.html
Script output - known fields:
1003 token-ring-default trcrf 1500 101003 1004 fddinet-default fdnet 1500 101004 1005 trnet-default trbrf 1500 101005
Script output - unknown fields:
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x07\x07\x00\x00\x00' b'\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' b'\x00\x00\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
show vlan output:
1003 tr 101003 1500 - - - - srb 0 0 1004 fdnet 101004 1500 - - 1 ieee - 0 0 1005 trnet 101005 1500 - - 1 ibm - 0 0
Cisco Docs input
show vlan fields
You can set these parameters when you create a new normal-range VLAN or modify an existing VLAN in the VLAN database:
- VLAN ID
- VLAN name
- VLAN type
- Ethernet
- Fiber Distributed Data Interface [FDDI]
- FDDI network entity title [NET]
- TrBRF or TrCRF
- Token Ring
- Token Ring-Net
- VLAN state (active or suspended)
- Maximum transmission unit (MTU) for the VLAN
- Security Association Identifier (SAID)
- Bridge identification number for TrBRF VLANs
- Ring number for FDDI and TrCRF VLANs
- Parent VLAN number for TrCRF VLANs
- Spanning Tree Protocol (STP) type for TrCRF VLANs
- VLAN number to use when translating from one VLAN type to another
Information in IOS
VLAN Information
affe#sh vl VLAN Name Status Ports ---- -------------------------------- --------- ------------------------------- 1 default active Gi1/0/1, Gi1/0/2, Gi1/0/3, Gi1/0/4, Gi1/0/22, Gi1/0/23, Gi1/0/25, Gi1/0/26 3 VLAN0003 active 5 VLAN0005 active 50 Affe active 52 Banane active Gi1/0/13, Gi1/0/14 915 Entensuppe 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 - - - - - 0 0 VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2 ---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------ 3 enet 100003 1500 - - - - - 0 0 5 enet 100005 1500 - - - - - 0 0 50 enet 100050 1500 - - - - - 0 0 52 enet 100052 1500 - - - - - 0 0 915 enet 100915 1500 - - - - - 0 0 1002 fddi 101002 1500 - - - - - 0 0 1003 tr 101003 1500 - - - - srb 0 0 1004 fdnet 101004 1500 - - 1 ieee - 0 0 1005 trnet 101005 1500 - - 1 ibm - 0 0 Remote SPAN VLANs ------------------------------------------------------------------------------ Primary Secondary Type Ports ------- --------- ----------------- ------------------------------------------
VTP Configuration / Status
affe#sh vtp status VTP Version capable : 1 to 3 VTP version running : 1 VTP Domain Name : ENTENSUPPE VTP Pruning Mode : Disabled VTP Traps Generation : Disabled Device ID : a2a3.2b63.ef21 Configuration last modified by 192.168.2.230 at 10-21-16 16:41:50 Local updater ID is 192.168.1.200 on interface Vl1 (lowest numbered VLAN interface found) Feature VLAN: -------------- VTP Operating Mode : Server Maximum VLANs supported locally : 255 Number of existing VLANs : 42 Configuration Revision : 321 MD5 digest : 0x00 0x11 0x22 0x33 0x44 0x55 0xE4 0x66 0x77 0x88 0x99 0xAA 0xBB 0xCC 0xDD 0xEE
Abbreviations
Abbreviation | written-out |
---|---|
BRF | Bridge Relay Function |
TrCRF | Token Ring Concentrator Relay Function |
TrBRF | Token Ring Bridge Relay Function |
Links
- Description of VLAN fieldsCatalyst 2960-X Switch VLAN Configuration Guide, Cisco IOS Release 15.0(2)EX
1)
for number of iterations see Number of existing VLANs from above
os/ios/vlan.dat.1478959428.txt.gz · Last modified: 2016-11-12 15:03 by root