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GLBP

HumperHumper Member Posts: 647
Couple questions regarding the weighting in GLBP.

When you want to configure tracking for an interface, you use the following command:
track <object-number> interface <type & #> {line protocol | ip routing}

Now the object number, is that the same as the group number or just a locally significant unrelated value? From what I understand this command set the interface you want to track and what you want it to track (line protocol / ip routing) correct??

Now to setup the weighting value on the interface you use the
glbp <group #> weighting <maximum> [lower <value>] [upper <upper>]

So this command sets the initial weighting value and the upper and lower thresholds? I am confused what they mean by upper and lower. Can someone elaborate for me?

The next command is
glbp <group#> weighting track <object#> decrement <value>

This specifies the object / interface to be tracked? The decrement means to decrement the weighting value we set above? So if the initial weighting was 100 and we said to decrement by 5 if there was a problem with the interface/routing it would drop to 95? How does this work with the upper and lower thresholds?

What I just read in another document is that there are 4 ways to load balance (none,weighted,host dependent, round-robin)..So I guess what I am discussing above is the weighted way of load balancing.

Here are the documents I was referencing:
http://www.cisco.com/en/US/products/ps6350/products_configuration_guide_chapter09186a008042fb97.html
http://www.cisco.com/en/US/products/ps6600/products_data_sheet0900aecd803a546c.html
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    HumperHumper Member Posts: 647
    Is there something I am missing in my post?
    Now working full time!
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    HELLZxPHADERHELLZxPHADER Member Posts: 74 ■■□□□□□□□□
    heres my glbp configuration from a while back, its better to keep glbp simple, it works well as long as u got preempt enabled, i think lol.

    2620(cable), 2621(dsl) both are connected to the switch(3550) on vlan4 and below are the cfg for each.

    version 12.3
    service timestamps debug datetime msec
    service timestamps log datetime msec
    service password-encryption
    !
    hostname 2620
    !
    no aaa new-model
    ip subnet-zero
    ip cef
    !
    !
    ip dhcp pool cable
    import all
    network 10.6.6.0 255.255.255.0
    default-router 10.6.6.253
    dns-server 4.2.2.2 4.2.2.3
    !
    !
    !
    !
    track 30 interface Ethernet1/0 line-protocol
    delay up 30
    !
    !
    interface FastEthernet0/0
    description to 3550 vlan4
    ip address 10.6.6.253 255.255.255.0
    ip nat inside
    duplex auto
    speed auto
    glbp 1 ip 10.6.6.254
    glbp 1 priority 105
    glbp 1 weighting 200
    glbp 1 weighting track 30
    glbp 1 forwarder preempt delay minimum 0
    !
    interface Serial0/2
    ip address 20.20.20.1 255.255.255.252
    clock rate 4000000
    !
    interface Ethernet1/0
    description cable
    ip address xx.xx.xx.70 255.255.255.0
    ip nat outside
    half-duplex
    !
    !
    ip nat pool cable xx.xx.xx.70 xx.xx.xx.70 netmask 255.255.255.0
    ip nat inside source static tcp 10.6.6.16 3389 interface Ethernet1/0 3389
    ip nat inside source route-map cable pool cable overload
    ip http server
    ip classless
    ip route 0.0.0.0 0.0.0.0 xx.xx.xx.1
    !
    !
    access-list 1 permit 10.6.6.0 0.0.0.255
    route-map cable permit 10
    match ip address 1
    match interface Ethernet1/0
    !
    !
    line con 0
    line aux 0
    line vty 0 4
    privilege level 15
    password 7 11011C091B08
    login
    !
    !
    end
    ___________________________________________________________

    version 12.3
    service timestamps debug uptime
    service timestamps log uptime
    service password-encryption
    !
    hostname 2621
    !
    enable password 7 030C5E070A15
    !
    no aaa new-model
    ip subnet-zero
    ip cef
    !
    !
    no ip domain lookup
    no ip dhcp conflict logging
    !
    ip dhcp pool dsl
    import all
    network 10.6.6.0 255.255.255.0
    default-router 10.6.6.252
    dns-server 4.2.2.2 4.2.2.3
    !
    !
    !
    !
    track 30 interface FastEthernet0/0 line-protocol
    !
    !
    interface FastEthernet0/0
    description dsl
    ip address 192.168.1.97 255.255.255.0
    ip nat outside
    duplex auto
    speed auto
    !
    interface Serial0/0
    ip address 20.20.20.2 255.255.255.252
    !
    interface FastEthernet0/1
    description to 3550 vlan4
    ip address 10.6.6.252 255.255.255.0
    ip nat inside
    duplex auto
    speed auto
    glbp 1 ip 10.6.6.254
    glbp 1 weighting 110
    glbp 1 weighting track 30
    glbp 1 forwarder preempt delay minimum 0
    !
    !
    ip nat pool dsl 192.168.1.97 192.168.1.97 netmask 255.255.255.0
    ip nat inside source static tcp 10.6.6.1 3389 interface FastEthernet0/0 3389
    ip nat inside source route-map dsl pool dsl overload
    ip http server
    ip classless
    ip route 0.0.0.0 0.0.0.0 192.168.1.1
    !
    !
    access-list 1 permit 10.6.6.0 0.0.0.255
    route-map dsl permit 10
    match ip address 1
    match interface FastEthernet0/0
    !
    !
    line con 0
    line aux 0
    line vty 0 4
    exec-timeout 16 0
    privilege level 15
    password 7 1211001B1E11
    login
    !
    !
    end

    ___________________________________________________________
    version 12.2
    no service pad
    service timestamps debug uptime
    service timestamps log uptime
    service password-encryption
    !
    hostname 3550
    !
    !
    no aaa new-model
    ip subnet-zero
    ip routing
    !
    !
    !
    no file verify auto
    spanning-tree mode pvst
    spanning-tree extend system-id
    !
    vlan internal allocation policy ascending
    !
    !
    interface FastEthernet0/1
    switchport mode dynamic desirable
    !
    interface FastEthernet0/25
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/26
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/27
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/28
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/29
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/30
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/31
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/32
    switchport access vlan 4
    switchport mode access
    spanning-tree portfast
    !
    interface FastEthernet0/48
    no switchport
    no ip address
    !
    interface GigabitEthernet0/1
    switchport mode dynamic desirable
    !
    interface GigabitEthernet0/2
    switchport mode dynamic desirable
    !
    interface Vlan1
    no ip address
    !
    interface Vlan2
    no ip address
    !
    interface Vlan3
    no ip address
    !
    interface Vlan4
    ip address dhcp
    !
    interface Vlan5
    no ip address
    !
    ip classless
    ip http server
    ip http secure-server
    !
    !
    !
    control-plane
    !
    !
    line con 0
    line vty 0 4
    privilege level 15
    password 7 060E0A2D4054
    login
    line vty 5 15
    privilege level 15
    password 7 10460C15090D
    login
    !
    end
  • Options
    HELLZxPHADERHELLZxPHADER Member Posts: 74 ■■□□□□□□□□
    And herez the show glbp from both routers.

    2620#show glbp
    FastEthernet0/0 - Group 1
    State is Active
    8 state changes, last state change 1d12h
    Virtual IP address is 10.6.6.254
    Hello time 3 sec, hold time 10 sec
    Next hello sent in 0.876 secs
    Redirect time 600 sec, forwarder time-out 14400 sec
    Preemption disabled
    Active is local
    Standby is 10.6.6.252, priority 100 (expires in 8.568 sec)
    Priority 105 (configured)
    Weighting 200 (configured 200), thresholds: lower 1, upper 200
    Track object 30 state Up decrement 10
    Load balancing: round-robin
    There are 2 forwarders (1 active)
    Forwarder 1
    State is Active
    7 state changes, last state change 13:52:33
    MAC address is 0007.b400.0101 (default)
    Owner ID is 00d0.5861.5920
    Redirection enabled
    Preemption enabled, min delay 0 sec
    Active is local, weighting 200
    Arp replies sent: 17
    Forwarder 2
    State is Listen
    4 state changes, last state change 14:15:19
    MAC address is 0007.b400.0102 (learnt)
    Owner ID is 0002.fd94.63c1
    Redirection enabled, 597.348 sec remaining (maximum 600 sec)
    Time to live: 14397.348 sec (maximum 14400 sec)
    Preemption enabled, min delay 0 sec
    Active is 10.6.6.252 (primary), weighting 110 (expires in 7.344 sec)
    Arp replies sent: 12
    2620#20.20.20.2
    Trying 20.20.20.2 ... Open
    ___________________________________________________________
    User Access Verification

    Password:
    2621#show glbp
    FastEthernet0/1 - Group 1
    State is Standby
    1 state change, last state change 14:15:20
    Virtual IP address is 10.6.6.254
    Hello time 3 sec, hold time 10 sec
    Next hello sent in 1.692 secs
    Redirect time 600 sec, forwarder time-out 14400 sec
    Preemption disabled
    Active is 10.6.6.253, priority 105 (expires in 7.996 sec)
    Standby is local
    Priority 100 (default)
    Weighting 110 (configured 110), thresholds: lower 1, upper 110
    Track object 30 state Up decrement 10
    Load balancing: round-robin
    There are 2 forwarders (1 active)
    Forwarder 1
    State is Listen
    2 state changes, last state change 13:52:44
    MAC address is 0007.b400.0101 (learnt)
    Owner ID is 00d0.5861.5920
    Time to live: 14397.992 sec (maximum 14400 sec)
    Preemption enabled, min delay 0 sec
    Active is 10.6.6.253 (primary), weighting 200 (expires in 7.988 sec)
    Forwarder 2
    State is Active
    1 state change, last state change 14:15:30
    MAC address is 0007.b400.0102 (default)
    Owner ID is 0002.fd94.63c1
    Preemption enabled, min delay 0 sec
    Active is local, weighting 110
    2621#exit
  • Options
    mikej412mikej412 Member Posts: 10,086 ■■■■■■■■■■
    Is there something I am missing in my post?

    No -- it just brings back bad memories....

    If you talk about "luck of the draw" on questions -- I was very unlucky with this blueprint topic. Someone else who took the exam not long after me was lucky.
    # Describe and configure gateway redundancy protocols (e.g. HSRP and GLBP)

    This could be a topic to double check your troubleshooting techniques.... and maybe pay extra attention to debug commands.
    :mike: Cisco Certifications -- Collect the Entire Set!
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