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Forum Discussion

Muhannad's avatar
Muhannad
Icon for Cirrus rankCirrus
Oct 17, 2022
Solved

Rewrite Subdomain

Dears, I am wondering about an efficient procedure to search and replace a specific Subdomain in the HOST, What i want to achieve is rewrite the HTTP request toward the server side as follows: Clie...
application delivery
  • CA_Valli's avatar
    CA_Valli
    Oct 17, 2022

    Code above is case sensitive on HTTP::host match. 

    If you want a case-insensitive match you can run this instead

    when HTTP_REQUEST {
#    log local0. "Client requested host: [HTTP::host]"
  if { [string tolower [HTTP::host]] starts_with "dir" && [string tolower [HTTP::host]] contains "clust1" }{
    HTTP::header replace Host [string map {"clust1" "clust2"}[string tolower [HTTP::host]]]
#        log local0. "Modified host: [HTTP::host]"
  }
}

     

    Oct 17 15:43:07 bigip info tmm7[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Client requested host: DIR000.Clust1.Domain.com
Oct 17 15:43:07 bigip info tmm7[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Modified host: dir000.clust2.domain.com
CA_Valli's avatar
CA_Valli
Icon for MVP rankMVP
Oct 17, 2022
when HTTP_REQUEST {
  if { [HTTP::host] starts_with "DIR" && [HTTP::host] contains "Clust1" }{
  HTTP::header replace Host [string map {"Clust1" "Clust2"}[HTTP::host]]
  }
}

 

Sample execution logs: 

Oct 17 15:32:37 bigip info tmm[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Client requested host: DIRx.Clust1.Domain.com
Oct 17 15:32:37 bigip info tmm[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Modified host: DIRx.Clust2.Domain.com
Oct 17 15:32:41 bigip info tmm6[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Client requested host: DIRy.Clust1.Domain.com
Oct 17 15:32:41 bigip info tmm6[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Modified host: DIRy.Clust2.Domain.com
Oct 17 15:32:43 bigip info tmm6[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Client requested host: DIRz.Clust1.Domain.com
Oct 17 15:32:43 bigip info tmm6[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Modified host: DIRz.Clust2.Domain.com

 

  • CA_Valli's avatar
    CA_Valli
    Icon for MVP rankMVP
    Oct 17, 2022

    Code above is case sensitive on HTTP::host match. 

    If you want a case-insensitive match you can run this instead

    when HTTP_REQUEST {
#    log local0. "Client requested host: [HTTP::host]"
  if { [string tolower [HTTP::host]] starts_with "dir" && [string tolower [HTTP::host]] contains "clust1" }{
    HTTP::header replace Host [string map {"clust1" "clust2"}[string tolower [HTTP::host]]]
#        log local0. "Modified host: [HTTP::host]"
  }
}

     

    Oct 17 15:43:07 bigip info tmm7[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Client requested host: DIR000.Clust1.Domain.com
Oct 17 15:43:07 bigip info tmm7[11345]: Rule /Common/test-iRule <HTTP_REQUEST>: Modified host: dir000.clust2.domain.com
    • Muhannad's avatar
      Muhannad
      Icon for Cirrus rankCirrus
      Oct 19, 2022

      This is working perfectly thanks :).

    • LiefZimmerman's avatar
      LiefZimmerman
      Icon for Admin rankAdmin
      Oct 25, 2022

      "Working perfectly!" so good.

      And...if I'm reading this right... CA_Valli - you had this solution in place only 2hrs after Muhannad asked? and in the middle of the night (for me on the west coast of US)?

      Thank you for your perfection & speed!
      ⏩🚀

      • CA_Valli's avatar
        CA_Valli
        Icon for MVP rankMVP
        Oct 26, 2022

        LiefZimmerman I'm based in europe so I was well awake and coffe-fueled 😉