RE: Question about -m tos option

RE: Question about -m tos option

[Rinse Kloek]

You need to patch iptables with the DSCP-target patch. Then you can use the
DSCP target to set all TOS values.

regards Rinse

-----Oorspronkelijk bericht-----
Van: Pavel V. Yanchenko [mailto:balrog@mail.ru]
Verzonden: donderdag 19 juni 2003 19:41
Aan: netfilter@lists.netfilter.org
Onderwerp: Question about -m tos option


Hello.

I need to create a rule matching packets with 0x60 value of TOS field.
The standard tos option of iptables doesn't accept such value, as well
as dscp, which is extension to tos - it processes only 6 bits of TOS
field :(
I guess value 0x60 is precedence bits...

The question is: how can I match such packets?

Thanks in advance.

  

Best regards,
 Pavel                          mailto:balrog@mail.ru

Re:Question about -m tos option

[Pavel V. Chjen]

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0x60 is out of valid range in dscp matching (:
[root@root linux]# iptables -A FORWARD -m dscp --dscp 0x60
iptables v1.2.9rc1: DSCP `96` out of range


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Re: Question about -m tos option

[Bill Chappell]

> "Pavel V. Chjen" wrote:
> 
> 0x60 is out of valid range in dscp matching (:
> [root@root linux]# iptables -A FORWARD -m dscp --dscp 0x60
> iptables v1.2.9rc1: DSCP `96` out of range

You only have 6 bits of the 8 bits in the ToS to work with
for DSCP,
(http://www.cisco.com/warp/public/105/dscpvalues.html#dscpandassuredforwardingclasses)
and valid values are explicitly 0 through 63 (decimal)
(http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fqos_r/qrfcmd4.htm#1098678).

Your rule used 60(hex),
which is 96(decimal) as the error message reported.


I got these references, and more, to confirm what
I thought I knew about DSCP by asking Google
for DSCP and DSCP+size, if that helps for the future.
(www.google.com)


I hope this helps and that you really do not
need 96 different values for the DSCP.

Bill


-- 
William Chappell,     Software Engineer,     Critical Technologies, Inc.
Suite 400 Technology Center, 4th Floor 1001 Broad Street, Utica, NY
13501
315-793-0248  x148  < bill.chappell@critical.com >  www.critical.com

Question about -m tos option

[Pavel V. Yanchenko]

Hello.

I need to create a rule matching packets with 0x60 value of TOS field.
The standard tos option of iptables doesn't accept such value, as well
as dscp, which is extension to tos - it processes only 6 bits of TOS
field :(
I guess value 0x60 is precedence bits...

The question is: how can I match such packets?

Thanks in advance.

  

Best regards,
 Pavel                          mailto:balrog@mail.ru