Hello Pros, I am working on a weird issue. Where customer is using BigIP 8900 11.2.1 HF10. While performing health-check for a customer, I observed that standby unit was showing some HTTP Connection in the QKview graphs. Since it is standby unit, it was a little surprising, and I requested for a remote session to validate the issue. I found that a few VS were showing "current connection" count to 2 or 5 in VS Statistics. Just out of curiosity I want to know that under which circumstances we can see such result? Thank you, Darshan

Hello Nitass, Nope, no connection mirroring is enabled on any of the VS/Persistence. However it seems enabled in HA configuration. What would be the impact of this configuration? If I only enable it in HA settings, but not on any VS or other objects. Apart from Mirroring, what else could be the possibility of this issue? Thank you, Darshan

What would be the impact of this configuration? If I only enable it in HA settings, but not on any VS or other objects. i understand connection is not mirrored until mirroring is enabled on virtual server. Apart from Mirroring, what else could be the possibility of this issue? not off top of my head. anyway, let us see what others say.

Standby Appliance receives HTTP Requests.

nitass_89166

Noctilucent

Dec 21, 2014

are you using connection mirroring?

e.g.

 configuration

[root@ve11a:Active:In Sync] config  tmsh list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    mirror enabled
    pool foo
    profiles {
        http { }
        tcp { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    vs-index 12
}
[root@ve11a:Active:In Sync] config  tmsh list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST {
  log local0. "hostname: [info hostname] \
    active: [HA::status active] standby: [HA::status standby] \
    client: [IP::client_addr]:[TCP::client_port]"
}
when HTTP_RESPONSE {
  log local0. "hostname: [info hostname] \
    active: [HA::status active] standby: [HA::status standby] \
    client: [IP::client_addr]:[TCP::client_port]"
}
}

 active

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) show ltm virtual bar raw

 (raw)
------------------------------------------------------------------
Ltm::Virtual Server: bar
------------------------------------------------------------------
Status
  Availability     : unknown
  State            : enabled
  Reason           : The children pool member(s) either don't have service checking enabled, or service check results are not available yet
  CMP              : enabled
  CMP Mode         : all-cpus
  Destination      : 172.28.24.10:80

Traffic                             ClientSide  Ephemeral  General
  Bits In                                 3312          0        -
  Bits Out                                4320          0        -
  Packets In                                 6          0        -
  Packets Out                                5          0        -
  Current Connections                        0          0        -
  Maximum Connections                        1          0        -
  Total Connections                          1          0        -
  Evicted Connections                        0          0        -
  Slow Connections Killed                    0          0        -
  Min Conn Duration/msec                     -          -      169
  Max Conn Duration/msec                     -          -      169
  Mean Conn Duration/msec                    -          -      169
  Total Requests                             -          -        1

SYN Cookies
  Status                         not-activated
  Hardware SYN Cookie Instances              0
  Software SYN Cookie Instances              0
  Current SYN Cache                          0
  SYN Cache Overflow                         0
  Total Software                             0
  Total Software Accepted                    0
  Total Software Rejected                    0
  Total Hardware                             0
  Total Hardware Accepted                    0

CPU Usage Ratio (%)
  Last 5 Seconds                             0
  Last 1 Minute                              0
  Last 5 Minutes                             0

[root@ve11a:Active:In Sync] config  tail -f /var/log/ltm
Dec 21 23:14:27 ve11a info tmm1[14890]: Rule /Common/qux : hostname: ve11a.acme.local  active: 1 standby: 0  client: 172.28.24.1:57671
Dec 21 23:14:27 ve11a info tmm1[14890]: Rule /Common/qux : hostname: ve11a.acme.local  active: 1 standby: 0  client: 172.28.24.1:57671

 standby

root@(ve11b)(cfg-sync In Sync)(Standby)(/Common)(tmos) show ltm virtual bar raw

 (raw)
------------------------------------------------------------------
Ltm::Virtual Server: bar
------------------------------------------------------------------
Status
  Availability     : unknown
  State            : enabled
  Reason           : The children pool member(s) either don't have service checking enabled, or service check results are not available yet
  CMP              : enabled
  CMP Mode         : all-cpus
  Destination      : 172.28.24.10:80

Traffic                             ClientSide  Ephemeral  General
  Bits In                                 3312          0        -
  Bits Out                                   0          0        -
  Packets In                                 6          0        -
  Packets Out                                0          0        -
  Current Connections                        0          0        -
  Maximum Connections                        1          0        -
  Total Connections                          1          0        -
  Evicted Connections                        0          0        -
  Slow Connections Killed                    0          0        -
  Min Conn Duration/msec                     -          -      268
  Max Conn Duration/msec                     -          -      268
  Mean Conn Duration/msec                    -          -      268
  Total Requests                             -          -        1

SYN Cookies
  Status                         not-activated
  Hardware SYN Cookie Instances              0
  Software SYN Cookie Instances              0
  Current SYN Cache                          0
  SYN Cache Overflow                         0
  Total Software                             0
  Total Software Accepted                    0
  Total Software Rejected                    0
  Total Hardware                             0
  Total Hardware Accepted                    0

CPU Usage Ratio (%)
  Last 5 Seconds                             0
  Last 1 Minute                              0
  Last 5 Minutes                             0

[root@ve11b:Standby:In Sync] config  tail -f /var/log/ltm
Dec 21 23:14:27 ve11b info tmm1[14917]: Rule /Common/qux : hostname: ve11b.acme.local  active: 0 standby: 1  client: 172.28.24.1:57671
Dec 21 23:14:27 ve11b info tmm1[14917]: Rule /Common/qux : hostname: ve11b.acme.local  active: 0 standby: 1  client: 172.28.24.1:57671

Shiraz_84431
Nimbostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby usnits when we have connection mirroring?

Mohammed
Shiraz_84431
Nimbostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby units when we have connection mirroring?

Regards,

Mohammed

nitass

Employee

Dec 21, 2014

are you using connection mirroring?

e.g.

 configuration

[root@ve11a:Active:In Sync] config  tmsh list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    mirror enabled
    pool foo
    profiles {
        http { }
        tcp { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    vs-index 12
}
[root@ve11a:Active:In Sync] config  tmsh list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST {
  log local0. "hostname: [info hostname] \
    active: [HA::status active] standby: [HA::status standby] \
    client: [IP::client_addr]:[TCP::client_port]"
}
when HTTP_RESPONSE {
  log local0. "hostname: [info hostname] \
    active: [HA::status active] standby: [HA::status standby] \
    client: [IP::client_addr]:[TCP::client_port]"
}
}

 active

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) show ltm virtual bar raw

 (raw)
------------------------------------------------------------------
Ltm::Virtual Server: bar
------------------------------------------------------------------
Status
  Availability     : unknown
  State            : enabled
  Reason           : The children pool member(s) either don't have service checking enabled, or service check results are not available yet
  CMP              : enabled
  CMP Mode         : all-cpus
  Destination      : 172.28.24.10:80

Traffic                             ClientSide  Ephemeral  General
  Bits In                                 3312          0        -
  Bits Out                                4320          0        -
  Packets In                                 6          0        -
  Packets Out                                5          0        -
  Current Connections                        0          0        -
  Maximum Connections                        1          0        -
  Total Connections                          1          0        -
  Evicted Connections                        0          0        -
  Slow Connections Killed                    0          0        -
  Min Conn Duration/msec                     -          -      169
  Max Conn Duration/msec                     -          -      169
  Mean Conn Duration/msec                    -          -      169
  Total Requests                             -          -        1

SYN Cookies
  Status                         not-activated
  Hardware SYN Cookie Instances              0
  Software SYN Cookie Instances              0
  Current SYN Cache                          0
  SYN Cache Overflow                         0
  Total Software                             0
  Total Software Accepted                    0
  Total Software Rejected                    0
  Total Hardware                             0
  Total Hardware Accepted                    0

CPU Usage Ratio (%)
  Last 5 Seconds                             0
  Last 1 Minute                              0
  Last 5 Minutes                             0

[root@ve11a:Active:In Sync] config  tail -f /var/log/ltm
Dec 21 23:14:27 ve11a info tmm1[14890]: Rule /Common/qux : hostname: ve11a.acme.local  active: 1 standby: 0  client: 172.28.24.1:57671
Dec 21 23:14:27 ve11a info tmm1[14890]: Rule /Common/qux : hostname: ve11a.acme.local  active: 1 standby: 0  client: 172.28.24.1:57671

 standby

root@(ve11b)(cfg-sync In Sync)(Standby)(/Common)(tmos) show ltm virtual bar raw

 (raw)
------------------------------------------------------------------
Ltm::Virtual Server: bar
------------------------------------------------------------------
Status
  Availability     : unknown
  State            : enabled
  Reason           : The children pool member(s) either don't have service checking enabled, or service check results are not available yet
  CMP              : enabled
  CMP Mode         : all-cpus
  Destination      : 172.28.24.10:80

Traffic                             ClientSide  Ephemeral  General
  Bits In                                 3312          0        -
  Bits Out                                   0          0        -
  Packets In                                 6          0        -
  Packets Out                                0          0        -
  Current Connections                        0          0        -
  Maximum Connections                        1          0        -
  Total Connections                          1          0        -
  Evicted Connections                        0          0        -
  Slow Connections Killed                    0          0        -
  Min Conn Duration/msec                     -          -      268
  Max Conn Duration/msec                     -          -      268
  Mean Conn Duration/msec                    -          -      268
  Total Requests                             -          -        1

SYN Cookies
  Status                         not-activated
  Hardware SYN Cookie Instances              0
  Software SYN Cookie Instances              0
  Current SYN Cache                          0
  SYN Cache Overflow                         0
  Total Software                             0
  Total Software Accepted                    0
  Total Software Rejected                    0
  Total Hardware                             0
  Total Hardware Accepted                    0

CPU Usage Ratio (%)
  Last 5 Seconds                             0
  Last 1 Minute                              0
  Last 5 Minutes                             0

[root@ve11b:Standby:In Sync] config  tail -f /var/log/ltm
Dec 21 23:14:27 ve11b info tmm1[14917]: Rule /Common/qux : hostname: ve11b.acme.local  active: 0 standby: 1  client: 172.28.24.1:57671
Dec 21 23:14:27 ve11b info tmm1[14917]: Rule /Common/qux : hostname: ve11b.acme.local  active: 0 standby: 1  client: 172.28.24.1:57671

Shiraz_84431
Nimbostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby usnits when we have connection mirroring?

Mohammed
Shiraz_84431
Nimbostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby units when we have connection mirroring?

Regards,

Mohammed

swo0sh_gt_13163
Altostratus
Dec 22, 2014
Hello Nitass,

Nope, no connection mirroring is enabled on any of the VS/Persistence. However it seems enabled in HA configuration.

What would be the impact of this configuration? If I only enable it in HA settings, but not on any VS or other objects.

Apart from Mirroring, what else could be the possibility of this issue?

Thank you, Darshan
nitass
Employee
Dec 22, 2014
What would be the impact of this configuration? If I only enable it in HA settings, but not on any VS or other objects.

i understand connection is not mirrored until mirroring is enabled on virtual server.

Apart from Mirroring, what else could be the possibility of this issue?

not off top of my head. anyway, let us see what others say.
swo0sh_gt_13163
Altostratus
Dec 22, 2014
Thanks Nitass!
Shiraz
Altostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby usnits when we have connection mirroring?

Mohammed
Shiraz
Altostratus
Jan 13, 2017
Hi Nitass,

I am using connection mirroring and I see the same number of connections for virtual servers on both standby and active units. I also checked using the tcpdump command and found that on standby device, I see all the IN packets and on active IN and OUT Packets. Is this normal to even have the packets flow replicated on standby units when we have connection mirroring?

Regards,

Mohammed

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