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Andre-Germany's avatar
Andre-Germany
Icon for Nimbostratus rankNimbostratus
May 12, 2015

smtp check

Hello,   I have in ltm a smtp check and the pool with the check is down. With tcpdump can´t see pakets to the nodes and in the debug log is whistled "error: couldn't open socket: host is unreachab...
application delivery
LTM
Brad_Parker's avatar
Brad_Parker
Icon for Cirrus rankCirrus
May 12, 2015

Since the host is unreachable you could have an ARP issue. Meaning, your LTM may not be able to resolve a MAC address for the node you are testing and therefore you are not ever sending a SYN packet to even open the connection.