Compaq AA-Q88CE-TE manual Network Transports, Specifying the Link Transport Protocol

Starting and Setting Up RTR

2.8 RTR ACP Virtual Memory Sizing

A minimum of 419430 Kbytes for heap data segment sizing

A minimum of 33555 Kbytes for core file size

A minimum of 8389 Kbytes for stack segment size

A minimum of 0 for CPU time

•On HPUX:

A minimum of 1024 open file descriptors

The START RTR qualifiers /LINK and /PROCESSES apply only to the OpenVMS platform and the determination of process quotas on UNIX platforms must be done through operating system handling of virtual memory sizing.

2.9 Network Transports

RTR supports multiple network transports with a default behaviour as follows:

If an attempt to create a network connection to a remote node fails, RTR retries the connection attempt using an alternate transport protocol if one is available. The order in which the supported transport protocols are used depends on the host operating system:

OpenVMS - first DECnet then TCP/IP.

All other platforms - first TCP/IP, then DECnet.

If a connection attempt fails on all available protocols, the connect fails and is retried at a later time starting again with the first transport protocol.

If an established link fails, RTR automatically initiates a reconnection of the link, starting with the first transport protocol for the platform, regardless of the transport employed when the link failed.

2.9.1 Specifying the Link Transport Protocol

It is possible to override the protocol failover mechanism by specifying the transport protocol to be employed for a link by naming links to include a transport selecting prefix. Prefixing links names with "tcp." and "dna." specifies TCP/IP or DECnet as the required transports respectively. Use of these prefixes causes the local node to employ only the specified transport protocol when attempting a connection on the link to which the prefix has been applied. Note that use of a protocol prefix on one node does not prevent a remote node from connecting using some other transport.

For example, to specify the facility ``FAX1'' that only uses the DECnet transport, two routers (``DNET1'' and ``DNET2''), two backends (``SRV1'' and ``SRV2'') and many frontends, use the following command:-

RTR> create facility FAX1 /frontend=(dna.FE1,dna.FE2,dna.FE3 ....)

/router=(dna.DNET1,dna.DNET2)

/backend=(dna.SRV1,dna.SRV2)

Creating a facility that uses only TCP/IP would use a command like this:-

RTR> create facility FINANCE /frontend=(tcp.client1,tcp.client2,tcp.client7 ....)

/router=(tcp.routr1,tcp.routr2)

/backend=(tcp.srv1,tcp.srv2)

Starting and Setting Up RTR 2–13