FireBrick FB6602, Руководство пользователя

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PPPoE
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concentrator cannot handle the larger packets (such as a bridge or a switch). For this reason the default
MTU is 1492.
10.2.2.2. Service and ac-name
The PPPoE protocol allows multiple services to be offered, and the service setting can be used to select which
is available. This is rarely needed and should be ignored unless you know what you are doing. If specified,
even as an empty string, then only matching services will be selected.
The name specified via the
ac-name
attribute is the name of the PPPoE endpoint (access controller). In some
cases there may be a choice of endpoints and setting this causes one to be selected by name. Again, this is rarely
needed, and if specified will only match the name you specify. On Be PPPoE lines, for example, you could
select a specific LAC by name if you wanted to.
10.2.2.3. Logging
The PPP connection status, and PPP negotiation can be logged by setting the
log
attribute to a valid log target.
This can be useful for debugging.
10.2.2.4. Speed and graphs
As discussed in Chapter 9, graphs allow you to visual connections, in terms of their state, traffic rates and
patterns etc. By setting the
graph
attribute, you can cause the state of the line, data transferred each way, and
current packet loss and latency to be recorded on a graph. This normally operates in slow mode (an LCP every
16 seconds) but by setting the
slow
attribute to
false
you can monitor a line every second. **TBC is this
correct ; do we not use lcp-rate now?**
Once you are graphing the PPPoE connection, you can set traffic shaping to control speed (see Section 9.1.2).
Alternatively, a PPPoE connection is something you can set a speed limit on directly - setting the
speed
attribute will control the speed of traffic sent to the Internet - this is mainly used when bonding PPP links.