Filed under: notes/General
Just switched to fiber optic connection from ADSL for the sake stability. The UTP cables could be the bottleneck in achieving the often reported actual speed of around 20Mbps, so I checked the UTP cable specifications. The conclusion is, for 10Mbps category 4 is enough. For 100Mbps, Category 5 or newer is necessary. For gigabit (1000Mbps), Category 5 enhanced is necessary. Needless to say, in order to achieve maximum speed with 1000Mbps cable a gigabit NIC (and hub) is necessary.
CAT 3, 4, 5, 5e, 6, 7 Cable Specifications:
|
Category |
Type |
Spectral B/W |
Length |
LAN Applications |
Notes |
|
Cat3 |
UTP |
16 MHz |
100m |
10Base-T, 4Mbps |
Telephone Cables |
|
Cat4 |
UTP |
20 MHz |
100m |
16Mbps |
Rarely Used |
|
Cat5 |
UTP |
100MHz |
100m |
100Base-Tx,ATM, CDDI |
LAN |
|
Cat5e |
UTP |
100MHz |
100m |
100Base-T |
LAN |
|
Cat6 |
UTP |
250MHz |
100m |
1000Base-T |
LAN |
|
Cat7 |
ScTP |
600MHz |
100m |
1000Base-T |
LAN |
Filed under: notes/General
When using mailing list based on EZMLM, by default the list will reject a posting to the list when it cannot find its address in the “To:” or “Cc:”. Therefore, any “BCC:” posting will be rejected.
This behavior can be changed by altering the option of “qmail-reject”. From “qmail-reject”‘s manual:
-t (Default.) Reject messages that do not have the
list address in the “To:” or “Cc:” header(s).
ezmlm-reject needs access to dir/outhost and
dir/outlocal to check this. This check is silently
omitted if dir is not specified, to assure back
wards compatibility with existing ezmlm lists.
-T Do not require the list address in the “To:” or
“Cc:” header(s).
So find the .qmail-[LISTNAME] file of the list LISTNAME, then change
|/usr/local/bin/ezmlm/ezmlm-reject [PATH]
to
|/usr/local/bin/ezmlm/ezmlm-reject -T [PATH]
