Forum Discussion
Destination address at F5
- Nov 06, 2022
Hi davidy2001 ,
> ICMP option is on virtual address list tab , see the below snap shot :Select your virtual server address and you will find the ICMP option and make it " disabled".
and try again.
> Or do it Cli ,
write this command on Tmsh prompt
( modify ltm virtual-address 10.0.30.254 icmp-echo disabled )
and try again
Look to this snap shot as well : - Nov 06, 2022
Hi davidy2001 ,
it is not weired , each virtual server is only responsible for its nodes and when you disable icmp echo on " 10.0.30.254" virtual server this option is related only to this virtual server , and other virtual servers do not impacted by your change , you will find the option of icmp-echo still as default always on all virtual servers except " 10.0.30.254 virtual server "
> For command , you wrote the command wrong , you need to write 10.0.30.254 instead of 10.0.30.1.
> this a special configuration for your environment , as the most deployed that F5 as a loadbalancer servers real servers not routers but of course everything is doable and available in F5 to handle your traffic on the way you want.
- my configuration was a workaround for your environment and " this virtual server 10.0.30.254" is the only object will be impacted to solve your issue with routes , and the rest of your applications and services run without impact.
Ty - Nov 07, 2022
davidy2001 ,
Also Note , When you change the virtual server IP only , the new virtual address added in statistics Page , Also you will find the in new virtual address the ( " icmp-echo" option returned to " always" ) again , so you will change it again.
> it is not good to change the virtual server ip address , you can create a new one instead of swapping ip , because existance of active session.
> Also , if you follow the scenario of swapping virtual server ip , run this command
" show sys connection cs-server-addr" , it will show to you that the traffic flow is correct and as expected.
Ty - Nov 07, 2022
davidy2001In all honesty if you are trying to figure out how the BIG-IP works I would configure VMs behind it rather than routers because it seems like you would want to use the BIG-IP in the closest way you intend to in the future. Most deployments of the BIG-IPs are for websites and applications rather than ICMP to routers. Don't get me wrong here because you can do all sorts of things on the BIG-IP but if your intent is to learn it I think the best way to start is the closest thing that everyone typically uses them for which is application load balancing or website load balancing. You can perform tcpdumps on the BIG-IPs to see traffic traversing it as well as a wireshark (windows) or tcpdump (linux) on the destination servers to see the traffic flow. This is a great exercise that you posted just to learn something one off but not where I would have started to learn about them.
- Nov 15, 2022
Hi davidy2001 ,
How are you ,
> you need to remove TCP profile and choose all protocols , because you are transferring icmp packets not a connection based on TCP :
check the below snap shot and tell me your feedback :Hope this help you and waiting your response.
HI davidy2001 ,
this is the IP address of your Virtual server , it is owned by F5 Big-ip itself.
> this IP is the real representation of your service.
> this IP is the destination IP which located in IP L3 Packet as a destination IP and a destination NAT happen to it.
Let me Explain :
for example we have a client ip/or user ip = 200.200.200.200 as a source outside F5 , and you configure this IP 10.0.30.254 as a destination address on F5 , also Asume that Pool_member or server address ip = 10.20.20.20
> the traffic flow should be as below :
Source ip : 200.200.200.200 " Client IP "
Destination IP : 10.0.30.254 " Destination IP on F5 or what we call it Virtual server IP "
that was the first half or oustide F5 connection or we call it connection between client side connection and F5.
after That F5 will perform a destination NAT to this IP "10.0.30.254" and converts it to "10.20.20.20"
So the traffic flow will be :
Source ip : 200.200.200.200 " Client IP "
Destination IP : 10.20.20.20 " Real server/or pool_member IP" After F5 Nat it.
That was the second half of F5 connection or we say that the inside connection between F5 and servers
> Note , I asume the default behavior of F5 without any additional configuration such as SNAT , or Virtual server type " full proxy or half proxy ".
briefly , this ip is the Virtual server IP , it can be single ip or subnet depend on your environment.
Regards
Mohamed Kansoh.
Recent Discussions
Related Content
* Getting Started on DevCentral
* Community Guidelines
* Community Terms of Use / EULA
* Community Ranking Explained
* Community Resources
* Contact the DevCentral Team
* Update MFA on account.f5.com