Hello QNXers,
I’ve been initializing a number of our embedded systems which include an
ethernet network controller and noticed the following strange behavior:
The first unit which I booted and initialized was able to be “pinged” by my
QNX development box without any problem. I then moved on to the the 2nd
embedded device and proceeded to initialize it and wanted to test the
ethernet connection with “ping”. This time it failed.
All the embedded devices will have the same IP address, but are never
running at the same time, so there shouldn’t be any address conflicts, as
far as I know. I searched and searched, trying to see if there were
problems with the embedded devices, but couldn’t find anything. Just for
the heck of it I tried pinging the embedded device from my Windows box, and
it worked!
I have also seen that the qnet connection is ok, but anything that uses the
IP address (FTP, Telnet, etc) won’t work from my QNX development box. After
rebooting my QNX development box, I was able to once again use ping, but
only once! As soon as I moved to another embedded device the problems
started from the top again.
Has anyone ever noticed something like this?
Is there something that needs to be done to “reset” the system to be able to
resolve IP addresses?
Most likely I’m making some big mistake. Please let me know if anything
occurs to you which might explain this.
Best regards,
Jason
The mac address corresponding to the ip addressed is
cached.
To see what’s in the cache:
arp -an
To delete the cached entry so it can be re-learned:
arp -d <ip_addr>
Or if you ping from the embedded box first, the old one
will be overwritten.
-seanb
Jason Wycoff <jason@socratec.de> wrote:
Hello QNXers,
I’ve been initializing a number of our embedded systems which include an
ethernet network controller and noticed the following strange behavior:
The first unit which I booted and initialized was able to be “pinged” by my
QNX development box without any problem. I then moved on to the the 2nd
embedded device and proceeded to initialize it and wanted to test the
ethernet connection with “ping”. This time it failed.
All the embedded devices will have the same IP address, but are never
running at the same time, so there shouldn’t be any address conflicts, as
far as I know. I searched and searched, trying to see if there were
problems with the embedded devices, but couldn’t find anything. Just for
the heck of it I tried pinging the embedded device from my Windows box, and
it worked!
I have also seen that the qnet connection is ok, but anything that uses the
IP address (FTP, Telnet, etc) won’t work from my QNX development box. After
rebooting my QNX development box, I was able to once again use ping, but
only once! As soon as I moved to another embedded device the problems
started from the top again.
Has anyone ever noticed something like this?
Is there something that needs to be done to “reset” the system to be able to
resolve IP addresses?
Most likely I’m making some big mistake. Please let me know if anything
occurs to you which might explain this.
Best regards,
Jason
Are there library calls to accomplish the check and delete functions?
–
Jeff Maass jmaass@columbus.rr.com Located near Columbus Ohio
USPSA # L-1192 NROI/CRO Amateur Radio K8ND
Maass’ IPSC Resources Page: http://home.columbus.rr.com/jmaass
“Sean Boudreau” <seanb@qnx.com> wrote in message
news:ahp1jb$bnv$1@nntp.qnx.com…
The mac address corresponding to the ip addressed is
cached.
To see what’s in the cache:
arp -an
To delete the cached entry so it can be re-learned:
arp -d <ip_addr
Or if you ping from the embedded box first, the old one
will be overwritten.
-seanb
Jason Wycoff <> jason@socratec.de> > wrote:
Hello QNXers,
I’ve been initializing a number of our embedded systems which include an
ethernet network controller and noticed the following strange behavior:
The first unit which I booted and initialized was able to be “pinged” by
my
QNX development box without any problem. I then moved on to the the 2nd
embedded device and proceeded to initialize it and wanted to test the
ethernet connection with “ping”. This time it failed.
All the embedded devices will have the same IP address, but are never
running at the same time, so there shouldn’t be any address conflicts,
as
far as I know. I searched and searched, trying to see if there were
problems with the embedded devices, but couldn’t find anything. Just
for
the heck of it I tried pinging the embedded device from my Windows box,
and
it worked!
I have also seen that the qnet connection is ok, but anything that uses
the
IP address (FTP, Telnet, etc) won’t work from my QNX development box.
After
rebooting my QNX development box, I was able to once again use ping, but
only once! As soon as I moved to another embedded device the problems
started from the top again.
Has anyone ever noticed something like this?
Is there something that needs to be done to “reset” the system to be
able to
resolve IP addresses?
Most likely I’m making some big mistake. Please let me know if anything
occurs to you which might explain this.
Best regards,
Jason
Both stacks support the SIOC[GSD]ARP ioctls on the
/dev/io-net/ip_en device. In addition, the full
stack’s cache can be manipulated via routing sockets
smiilar to NetBSD.
-seanb
Jeff Maass <jmaass@columbus.rr.com> wrote:
Are there library calls to accomplish the check and delete functions?
–
Jeff Maass > jmaass@columbus.rr.com > Located near Columbus Ohio
USPSA # L-1192 NROI/CRO Amateur Radio K8ND
Maass’ IPSC Resources Page: > http://home.columbus.rr.com/jmaass