Do you want to increase system performance by adjusting TCP/IP parameters?
TCP/IP performance over an ATM network can be poor unless you carefully configure your network. Poor performance usually occurs because the TCP/IP packets are segmented into cells for transmission by the ATM software. Therefore, a loss of a single cell can cause the loss of an entire TCP/IP packet which can lead to retransmissions that congest the network. When it detects congestion, the destination system reduces the transmission rate, which significantly reduces the network performance.
You can achieve better network performance from the SunATM adapter and software by adjusting your application’s socket buffer size to 48 Kbytes. Refer to the application’s documentation for instructions on how to set the socket buffer size.
Are you trying to mount a diskless, dataless, or autoclient system?
The SunATM adapters do not currently support diskless, dataless, or autoclient systems. The root filesystem must be local for the SunATM adapter to operate.
Did the atmtest diagnostic fail?
If the bandwidth or outstanding packets value is set too high on your system, the SunVTS atmtest diagnostic can fail, giving an error similar to the following:
SUNWvts.atmtest.4000 09/17/98 17:33:10 atmtest ba0
WARNING: “VC30 dropped pkt, seq: exp=41, obs=43; len: exp=1747, obs=6022”
To correct this error, reduce the bandwidth or the number of outstanding packets in the SunVTS atmtest.
Appendix D Troubleshooting and SunATM Error Messages 109
