Digium TC400B, User Manual

Page: 31 / 44

Chapter 4
Questions and Answers
This chapter provides frequently asked questions as identified from
Digium Technical Support and possible resolutions. Multiple resources
are available to obtain more information about Asterisk and Digium
products. These resources are listed on page 32.
Q: My card can’t seem to reach its full channel count, why?
A: See next answer.
Q: Asterisk issues errors such as "rtp.c: Unable to allocate socket: Too
many open files." How can I prevent this?
A: Each call that uses a TC400 Series card for transcoding requires two
file handles. Increase the maximum number of open file descriptors
allowed on your system using the ulimit utility. First, log into a Linux
shell as the user running the asterisk process (i.e. usually root). Check the
current maximum by executing
ulimit -n
. Increase the maximum by
executing
ulimit -n [limit]
(e.g.
ulimit -n 32768
).
Q: Does my card take 1000 interrupts per second like my other Digium
cards?
A: A TC400 Series card only takes interrupts when it is in an active
transcoding state, and will not pull interrupts when it is idling. This is
different behavior than Digium analog and digital interface cards exhibit.
Q: Does my TC400 Series card serve as a DAHDI timing device?
A: No, a TC400 Series card cannot serve as a DAHDI timing device. If
you have no other Digium cards installed which can serve as a DAHDI
Digium, Inc. Page 31