Virtual IP issue in MC/SG cluster.

[nishith]

hello all,

i need a clarification on MC/SG virtual IP concept. recently i had setup MC/SG at a Bank for the ATM controller server running a legacy software. while the cluster is perfectly working fine. Now issue is with virtual IP ie., PACKAGE IP. whenever any clients access the server the network socket connection is established using the virtual ip. but for outbound traffic i.e., server initiating any network connection it uses the node ip rather than virtual ip. Since this an ATM controller server connecting to VISA & Master card Networks where the firewall policy is strict, whereby they only allow one IP address.
Is this the default behaviour of serviceguard package IP that it is used only for incoming network connections? can we make the virtual package IP to be be used for outbound network connections? One workaround looks like to using NAT for outbound. i believe there is not much to do in serviceguard configuration to sort out this. i would grateful if anyone can give me good suggestions.thanking in advance.

Below is my setup:

Node-1: 172.17.15.62
Node-2: 172.17.15.63
Package-IP: 172.17.15.70
-------------------------------------
"netstat -an " output:

incoming network conn:----- (uses virtual IP )
tcp 0 0 172.17.15.70.1712 172.17.15.10.49216 ESTABLISHED

outgoing network conn:----- (uses node IP)
tcp 0 0 192.168.1.62.47093 172.17.15.10.9004 ESTABLISHED

[nishith]

sorry typing error in netstat output
------------------------------------


"netstat -an " output:

incoming network conn:----- (uses virtual IP )
tcp 0 0 172.17.15.70.1712 172.17.15.10.49216 ESTABLISHED

outgoing network conn:----- (uses node IP)
tcp 0 0 172.17.15.62.47093 172.17.15.10.9004 ESTABLISHED

[Chan 007]

Hi,

I guess you might need to use "ndd" for tuning the IP stack.

Chan

[Torsten.]

Hi,

it looks like your host and your package are running on the same subnet. So your host "talks randomly" on both interfaces.

[Stephen Doud · Accepted solution]

outbound packets normally contain the fixed IP of the NIC that sends the message, unless

a) the application that generate the packet also modifies the outbound source IP.
See appendix C, pg 419 "Bind to Relocatable IP Addresses"
in the "Managing Serviceguard" manual:
http://docs.hp.com/en/B3936-90100/B3936-90100.pdf

b) create a route that forces the outbound packet to use the relocatable IP thus:

$ /usr/sbin/route add host target-ip gateway-ip