@startuml
repeat :send request;
:receive response;
backward :node1;
backward :node2;
repeat while (error?) is (try again)
@enduml
The second backward node overwrites the first one.
http://www.plantuml.com/plantuml/uml/NSqX4i8m48LXdrEiR2N8HD2hBCqRo52IydPBXjiJWy7-ulyMSwKVpoqGEzGb6ceMudN0F8L8h2XlZ69xguOKhhe-kZ9Bh2tZz1_EwRVgzx919f2DbrcAoUJyYDwqr3aimndk5m00