TCP IP Illustrated

298 no the nfs client can reuse the same local

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Unformatted text preview: ost in the network, the server's TCP will time out and retransmit the reply when it doesn't receive an ACK from the client's TCP. Eventually the segment will arrive at the client's TCP The difference here is that the two TCP modules do the timeout and retransmission, not the NFS client and server. (When UDP is used, the NFS client code performs the timeout and retransmission.) Therefore the NFS client never knows that the reply was lost and had to be retransmitted. 29.7 It is possible for the NFS server to obtain a different port number after the reboot. This would complicate the client, because it would have to know that the server crashed and contact the server's port mapper after the reboot to find the NFS server's new port number. This scenario, where the server crashes and reboots and a server RPC application obtains a new ephemeral port, can happen to any RPC application that doesn't use a well-known port. 29.8 No. The NFS client can reuse the same local, reserved port number for different servers. TCP requires the 4-tuple of local IP address, local port, foreign IP address, and foreign port to be unique, and the foreign IP address is different for each server host. Chapter 30 30.1 Type whois "net 88". Class A network IDs 64 through 95 are reserved. 30.2 Type whois whitehouse-dom. Either the host command or nslookup can query the DNS. 30.3 No, xscope can run on a different host from the server. If the hosts are different, then xscope can also use TCP port 6000 for its incoming connection. file:///D|/Documents%20and%20Settings/bigini/Doc...omenet2run/tcpip/tcp-ip-illustrated/append_d.htm (20 of 20) [12/09/2001 14.48.04] Appendix E: Configurable Options Configurable Options We've seen many features of TCP/IP that we've had to describe with the qualifier "it depends on the configuration." Typical examples are whether or not UDP checksums are enabled (Section 11.3), whether destination IP addresses with the same network ID but a different subnet ID are loc...
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