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Gibby69_345881's avatar
Gibby69_345881
Icon for Nimbostratus rankNimbostratus
Mar 10, 2018

modify tcp_half_open

I have several pools that monitor tcp_half_open and I would like to modify them so that they monitor tcp. So my goal is to remove the tcp_half_open on each pool and have it monitor tcp. Below is an example of that it looks like now: ltm pool ARCH_PE_DataJunction_arch_pe_DJport7110 { members { 20.20.142.68:7110 { address 20.20.142.68 session monitor-enabled state down } 20.20.142.69:7110 { address 20.20.142.69 session monitor-enabled state down } 20.20.142.70:7110 { address 20.20.142.70 session monitor-enabled state down } 20.20.142.71:7110 { address 20.20.142.71 session monitor-enabled state down } 20.20.142.72:7110 { address 20.20.142.72 session monitor-enabled state down } } monitor tcp_half_open }

 

I was wondering if anyone could supply me with what the syntax would look like to modify this without any issues.

 

1 Reply

  • It should be as simple as executing the following TMSH command:

    tmsh modify /ltm pool  monitor tcp
    `
    
    
    For example, to modify the pool you cited in your question:
    
    
    `tmsh modify /ltm pool ARCH_PE_DataJunction_arch_pe_DJport7110 monitor tcp
    

    As for whether changing the monitor will produce issues or not, there are always things to consider. The tcp_half-open monitor does a SYN/SYN-ACK followed by a RST. The tcp monitor does a full 3-way handshake (SYN/SYN-ACK/ACK) and then sends a FIN. This may have an impact in your environment as clearly the volume of traffic per monitor test is different.