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Vicky_371599's avatar
Vicky_371599
Icon for Nimbostratus rankNimbostratus
Sep 10, 2018

Migration of servers load balanced in BIG-IP LTM

Hi all,

 

I am new to this forum and I have this below query.

 

Let me give you a background. There are 2 organizations involved in this. Let us call them ABC and XYZ for time being. ABC(Source Org) - uses F5 in their network. XYZ(Target Org) - uses Citrix Netscaler.

 

The requirement is to migrate some applications (servers running those applications) in ABC to XYZ. There are Network connectivity and L3 routing in place between these organizations. After the migration, the servers will inherit new IP addresses in the XYZ. The migrated servers will be load balanced using Netscalers at a later stage.

 

Plan is Step 1. Migrate servers to XYZ and they will get new IPs. Step 2. Change F5 configuration at ABC, so that they continue to load balance using the servers with new IPs. Step 3. Migrate F5 configurations at ABC to Netscalers at XYZ, so servers start using LBs at XYZ and remove the dependency of LBs at ABC. My queries are 1. Can the migrated servers land in XYZ(with new IPs), still be load balanced by F5s in Org ABC over L3 connectivity for an interim period? if yes, what changed are required to be done in F5s at ABC?

 

  1. At a later stage how we can migrate the F5 configuration at ABC to Citrix Netscalers at XYZ? Are there any tools to migrate iRules, WAF settings etc.? Much appreciate your reply.

Thank you

 

BIG-IP
LTM
security
  • Philip_Jonsson's avatar
    Philip_Jonsson
    Icon for MVP rankMVP
    Sep 10, 2018

    1. Can the migrated servers land in XYZ(with new IPs), still be load balanced by F5s in Org ABC over L3 connectivity for an interim period? if yes, what changed are required to be done in F5s at ABC?

     

    Putting F5 in front of other network/security devices are usually no problem at all and I have not seen anywhere stating that you cannot put an F5 device in front of Citrix Netscaler. But with that said, since you have a complete new set up IP addresses, I'd rather just set up a replica of the application within the Citrix NetScaler environment and make sure that, load-balancing, iRules, WAF works completely, before making the move to NetScaler. When you're ready to move the application you can simply just change the DNS to point to the new NetScaler environment. If something fails you just change back the DNS to its original configuration.

     

    Why do you still need the F5 to be involved?

     

    2. At a later stage how we can migrate the F5 configuration at ABC to Citrix Netscalers at XYZ? Are there any tools to migrate iRules, WAF settings etc.? Much appreciate your reply.

     

    There are supposedly a conversion tool which the Citrix NetScaler SE's have. But the experience from other customers is that it's usually not that clean and might introduce weird problems. The suggestions state that you should set it up manually. Since you have iRules, converting those automatically is supposedly not a great idea. Check out this thread from the NetScaler forum: https://discussions.citrix.com/topic/235530-f5-to-netscaler-migration/

     

    But if it's still interesting, check with a Citrix SE. :)