Forum Discussion
NimbostratusGTM DNS response error
Hi everybody,
I am new in GTM configuration and I have some problems. Here is a little explanation of the architecture :
I'm using GTM in delegation for responding to a sub-zone extranet.example.com and particulary a gateway named ssl.extranet.example.com (which is a ssl server) Example.com is authoritative on another LocalDNS (on private subnet), I have configured this one for sending DNS request to the F5 GTM. I have 2 ISP and one server (ssl.extranet) which has 2 IP on each ISP.
My questions are : - When a client send a DNS request to ssl.extranet.example.com, I want the F5 send back the DNS response in function of the availability of each ISP. If the ISP1 is not available, I want to respond with the ISP2's IP address of the server. Is it possible ?
Here are the objects I have configured : I have configured on my GTM : - two listener on the public address space (1 UDP and 1 TCP) - 2 servers ( the 2 private IP of the ssl server) - 2 Virtual Server (one for each server) referecenced the 2 IP public addresses of the F5 for each ISP. - One Pool that referenced the 2 Virtual servers.
- One listener ssl.extranet.example.com - One zone extranet.example.com with SOA, NS and a A record associated to F5 configuration.
I have also associated basic gateway_icmp monitor on the object. On the ssh command line, all the ping request on my objects (server, vip, dns server, are OK. But on the F5 GUI, all the object are marked down. I don't know why.
Do you have some possible explanations ?
7 Replies
Cory_50405Noctilucent
Do you have the ICMP monitor assigned at the pool level, or at the server level?
bboyjnr_8532Cirrus
in answer to...
"When a client send a DNS request to ssl.extranet.example.com, I want the F5 send back the DNS response in function of the availability of each ISP. If the ISP1 is not available, I want to respond with the ISP2's IP address of the server. Is it possible ? "
This is possible with the "Global Availability" LB Method set on the WIP/GTM pool but will require monitoring set on the VS's.
julien_21453Hi Cory, The monitor is placed on the server.
Hi bboyjnr, Ok,I will check my GA configuration.
- Cory_50405Your objects being unavailable (red) from the GUI could be because of a number of reasons outside of the GTM configuration (routing, access control). Does your GTM have a route to your servers via a TMM (non-management) interface?
- julien_21453I don't have filter. I have the good routes on the F5 to my servers. I don't have LTM activated. On the VS, i'm seeing : "gtmd : no reply from big3d" But big3d is the LTM daemon, no ?
- Cory_50405Are your servers configured as Generic Host or BIG-IP System? They should be Generic Host. big3d daemon is used to communicate between F5 devices. This shouldn't come into play when attempting to run an ICMP keepalive.
