shithub: riscv

ref: b2cd4959fe3695d317b6b75956da55a7f77ed858
dir: /sys/man/8/cec/

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.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
] [
.I interface
]
.SH DESCRIPTION
.I Cec
uses raw Ethernet packets to connect to a CEC server for console access.
All clients share the same session.
Coraid appliances and Coraid Plan 9 kernels can currently be CEC servers.
.PP
.I Cec
starts by probing the specified network interface
for available CEC servers.  The default is
.BR /net/ether0 .
Only one
.I cec
process may be run per Ethernet interface.
If the server is specified with the
.BR -b ,
.BR -h ,
or
.B -s
options, communication 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
option is specified,
.I cec
exits if no matching servers are found.
The selection prompt accepts
.LP
.TF "\fInumber "
.TP
.I number
Connect to server
.I number
(from the first column),
.TP
.B p
Probe the interface again, and
.TP
.B q
Quit.
.PD
.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, typing the escape character
will drop the user into an escape prompt where the user may type
.L q
to quit the connection,
.L i
to send the escape character
across the connection, or
.L .
to continue the connection.
.SS Options
.TP
.B -c
Set the escape character to
.RI control- esc .
The default setting is control-\e.
.TP
.B -d
Print debugging information.
.TP
.B -e
Connect to the server with Ethernet address
.IR ea ;
implies
.BR -p .
.TP
.B -h
Connect to the server
.IR host .
Note that this name might not be the same as the contents of
.L /dev/sysname
on the target system.
.TP
.B -p
Persist: continue trying to connect even if
there are no matching servers.  This is useful when
connecting to a CPU server before it boots.
.TP
.B -s
Connect to the server at address
.IR shelf .
.TP
.B -S
Post the CEC connection as
.BI /srv/ srv
to allow sharing.
.PP
If the
.BR -e ,
.BR -s ,
or
.B -h
options are given,
.I cec
will exit upon closing the connection.
Otherwise,
.I cec
will return to the selection prompt upon connection close.
.SH EXAMPLES
.IP
.EX
; cec '#l1/ether1'
 0       1 003048679b89 
[#qp]: 0

SR shelf 1> 
SR shelf 1> >>> q
 0       1 003048679b89 
[#qp]: q
;
.EE
.SH SOURCE
.B /sys/src/cmd/cec
.\" .SH "SEE ALSO"
.\" .IR cec (3)
.SH BUGS
The CEC protocol should be integrated with the console server.
The arbitration between the keyboard and network is suboptimal.
.PP
Early boot information and very late crash information from servers
may be lost due to timing quirks.