.TH CEC 8
.SH NAME
cec \- Coraid Ethernet Console
.SH SYNOPSIS
.B cec
[
.B -dp
] [
.B -S
.I srv
] [
.B -c
.I esc
] [
.B -e
.I ea
] [
.B -h
.I host
[
.B -s
.I shelf
] [
.B interface
]
.SH DESCRIPTION
The
.I cec
command uses raw ethernet frames to connect to a CEC
server to simulate a serial connection.  The client and
protocol provide for packet acknowledgement and
retransmission.
Coraid appliances and Coraid Plan 9 kernels can currently be
CEC servers.  Each uses CEC to provide console access.
.PP
A
.I cec
process starts by probing the specified network interface
for available CEC servers.  The default is
.I /net/ether0 .
Only one
.I cec
process may be run per ethernet interface.  The
.B -S
flag posts its argument to
.B /srv
to allow sharing.
If the server is specified with the
.BR -b ,
.BR -h ,
or
.B -s
flag, the connection will
proceed immediately upon discovery of the first CEC server
with the specified address.  Otherwise, a selection prompt
will be displayed showing the discovered CEC servers 
available for communication.  Unless the
.B -p
flag is specified, 
.I cec
exits if no matching servers are found.
.IP
.EX
 0 5 003048865f1e shelf5
 [#qp]: 
.EE
.LP
The selection prompt accepts
.TP
.I n
Connect to server
.I n
(from the first column),
.TP
.B p
Probe the interface again, and
.TP
.B q
Quit.
.PP
Note the selection number is not the shelf address but the
.IR cec -generated
sequence number printed in the leftmost column.
.PP
Once connected to a cec server, entering the escape sequence
will drop the user into an escape prompt where the user may
type 'q' to quit the connection, 'i' to send the escape sequence
across the connection, or '.' to continue the connection.
The escape sequence is printed on connection.
If the connection is unexpectedly lost,
the initial probe process outlined above is rerun.
.SS Options
.TP 1i
.BI -c " esc"
Set the escape caracter to
.BI ctl -
.IR esc .
The default setting is
.BR ctl -\e.
.TP
.B -d
Output debugging information.
.TP
.BI -e " ea"
Connect to the server with ethernet address
.IR ea .  This option implies
.IR -p .
.TP
.BI -h " host"
Connect to the server named
.IR host .
Note this name may not be the same as the value of
.LR /dev/sysname .
.TP
.B -p
Persistence.  Continue trying to connect even if
there are no matching servers.  This is useful when
connecting to a cpu server before it boots.
.TP
.BI -s " shelf"
Connect to the server at shelf address
.IR shelf .
.SH "SEE ALSO"
.IR cec (3).
.SH BUGS
The CEC protocol should be integrated with the console server.
.PP
CEC should multiplex network connections as
.B /net/tcp
does.
.PP
Early boot information and very late crash information from servers
may be lost due to timing quirks.