# F5 ip-forward virtual-server to a10 vs configuration

**URL:** <https://community.a10networks.com/t/f5-ip-forward-virtual-server-to-a10-vs-configuration/766>\
**Category:** ADC - Application Delivery\
**Created:** [March 13, 2023, 7:10pm UTC](https://community.a10networks.com/t/f5-ip-forward-virtual-server-to-a10-vs-configuration/766 "2023-03-13T19:10:04Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Hugo\_Gomez](https://avatars.discourse-cdn.com/v4/letter/h/49beb7/32.png) [@Hugo\_Gomez](https://community.a10networks.com/u/Hugo_Gomez)\
**Post date:** [March 13, 2023, 7:10pm UTC](https://community.a10networks.com/t/f5-ip-forward-virtual-server-to-a10-vs-configuration/766/1 "2023-03-13T19:10:04Z")

</div>

Hi guys  
I’m asking for your help to clarify the use of the ip-forward option on F5 devices for virtual-servers, for me looks simple, but I didn’t use it before in our a10 devices

This is an example of the current configuration on F5 that I need to migrate:

}  
ltm virtual DNS\_Telefonica\_171 {  
&nbsp;&nbsp;description “Forwarding DNS 10.161.9.171”  
&nbsp;&nbsp;destination 10.161.9.171:domain  
&nbsp;&nbsp;ip-forward  
&nbsp;&nbsp;ip-protocol udp  
&nbsp;&nbsp;mask 255.255.255.255  
&nbsp;&nbsp;profiles {  
&nbsp;&nbsp;&nbsp;&nbsp;fastL4 { }  
&nbsp;&nbsp;}  
&nbsp;&nbsp;source 10.164.100.138/31  
&nbsp;&nbsp;source-address-translation {  
&nbsp;&nbsp;&nbsp;&nbsp;type automap  
&nbsp;&nbsp;}  
&nbsp;&nbsp;translate-address disabled  
&nbsp;&nbsp;translate-port disabled  
&nbsp;&nbsp;vs-index 3  
}  
ltm virtual LDAP\_TMVE\_171 {  
&nbsp;&nbsp;description LDAP\_TMVE\_171  
&nbsp;&nbsp;destination 10.161.9.171:any  
&nbsp;&nbsp;ip-forward  
&nbsp;&nbsp;mask 255.255.255.255  
&nbsp;&nbsp;profiles {  
&nbsp;&nbsp;&nbsp;&nbsp;fastL4 { }  
&nbsp;&nbsp;}  
&nbsp;&nbsp;source 10.164.100.138/31  
&nbsp;&nbsp;source-address-translation {  
&nbsp;&nbsp;&nbsp;&nbsp;type automap  
&nbsp;&nbsp;}  
&nbsp;&nbsp;translate-address disabled  
&nbsp;&nbsp;translate-port disabled  
&nbsp;&nbsp;vs-index 5  
}

I was searching and it seems I need to use a policy template with a forwarding-policy set, but it is not clear to me.

If you can guide me, I really appreciate it.

Kind regards,

---

<div class="post-metadata">

**Author:** ![mmartinez\_a10networks.com](https://avatars.discourse-cdn.com/v4/letter/m/d07c76/32.png) [@mmartinez\_a10networks.com](https://community.a10networks.com/u/mmartinez_a10networks.com)\
**Post date:** [March 14, 2023, 10:10am UTC](https://community.a10networks.com/t/f5-ip-forward-virtual-server-to-a10-vs-configuration/766/2 "2023-03-14T10:10:21Z")

</div>

Hi ,  
F5 LTM IP Forward features basically disables destination address translation and just forward the traffic to a specific IP.  
This is quite common to use this when using Direct Server Return (DSR) SLB Deployment.  
To Achieve the save in ACOS, we provide an option you can configure at Virtual Port level which is “no-dst-nat”, like in the following exemple:  
ACOS(config)#&nbsp; **slb virtual-server vip1 192.0.2.99** &nbsp;  
ACOS(config-slb vserver)#&nbsp; **port 80 tcp** &nbsp;  
ACOS(config-slb vserver-vport)#&nbsp; **service-group sg-web** &nbsp;  
ACOS(config-slb vserver-vport)#&nbsp; **no-dest-nat**  
You will find more information in our documentation here:

[Sign In | A10 Networks Product Documentation](https://documentation.a10networks.com/ACOS/521x/ACOS_5_2_1-P6/html/slb_Responsive_HTML5/Default.htm#slb/slb-deploy-l3dsr.htm%23slb-deploy-l3dsr_1490830921_1449711%3FTocPath%3DDirect%2520Server%2520Return%2520(DSR)%2520SLB%2520Deployment%7C _____ 0)  
A10 Network customers with a valid support contract can register for an account to download the latest firmware versions, FAQs, application notes, and technical documents. Log In RegisterBest Regards,