can't connect:no route to host.

Hi,now I am meeting a problem.

I ported the uClinux to the DE2 board.I used two DE2 boards to communicate with each other.One board is used as a server with its ip 192.168.135.6,the other is used as a client with its ip 192.168.135.10.My pc's ip is 192.168.135.9.

I can ping my pc with either DE2 board, and I can also ping each board with my pc.But I can't ping the DE2 board with the other.

so what is the problem?

I wrote a server.c and client.c .when I run server.c in the DE2 as the server,

I run the client.c in the DE2 as the client,and it displays"can't connect:no route to host."

I don't know why.I hope someone can help me .

below is the server.c and the client.c .they are simple.

/////server.c# include <sys/types.h># include <sys/socket.h># include <sys/ioctl.h># include <sys/time.h># include <netinet/in.h># include <arpa/inet.h># include <netdb.h># include <stdio.h># include <signal.h># include <unistd.h> # define FD_SETSIZE 1024

int main ()

{

int cd,sd;

struct sockaddr_in sin,cin;

char buf[1024];

int i,n;

fd_set rdfds,tsfds;

int res,fd,nread;

if((sd=socket(AF_INET,SOCK_STREAM,0))==-1)

{

perror("can&#39;t creat socket!");

exit(1);

}

sin.sin_family=AF_INET;

sin.sin_addr.s_addr=htonl(INADDR_ANY);

sin.sin_port=htons(1989);

if(bind(sd,(struct sockaddr*)&sin,sizeof(sin))==-1)

{

perror("bind error!");

exit(1);

}

if(listen(sd,20)==-1)

{

perror("listen error!");

exit(1);

}

FD_ZERO(&rdfds);

FD_SET(sd,&rdfds);

printf("waiting for connections from clients!\n");

while(1)

{

tsfds=rdfds;

res=select(FD_SETSIZE,&tsfds,0,0,0);

if(res<1)

{

perror("can&#39;t select!");

exit(1);

}

for(fd=0;fd<FD_SETSIZE;fd++)

{

if(FD_ISSET(fd,&tsfds))

{

if(fd==sd) //if it is listen descriptor;

{

if((cd=accept(sd,(struct sockaddr*)&cin,sizeof(cin)))==-1)

{

perror("accept error!");

exit(1);

}

FD_SET(cd,&rdfds);

printf("add client on fd%d",cd);

}

else

{

ioctl(fd,FIONREAD,&nread);

if(nread==0) //if client left

{

close(fd);

FD_CLR(fd,&rdfds);

printf("remove client on %d",fd);

}

else //data transfer

{

if((n=recv(cd,buf,sizeof(buf),0))<0)

{

perror("receive error!");

exit(1);

}

printf("received from the client:%s\n",buf);

for(i=0;i<=n;i++)

buf=toupper(buf);

if((n=send(cd,buf,sizeof(buf),0))<0)

{

perror("send error!");

exit(1);

}

}

}

}

}

}

}

///////////////////////client.c# include <sys/types.h># include <sys/socket.h># include <sys/ioctl.h># include <sys/time.h># include <netinet/in.h># include <arpa/inet.h># include <netdb.h># include <stdio.h># include <signal.h># include <unistd.h>

int main()

{

int sd;

struct sockaddr_in cin;

char buf[1024];

int n;

if((sd=socket(AF_INET,SOCK_STREAM,0))==-1)

{

perror("can&#39;t creat socket!");

exit(1);

}

cin.sin_family=AF_INET;

cin.sin_addr.s_addr=inet_addr("192.168.135.6");

cin.sin_port=htons(1989);

if(connect(sd,(void*)&cin,sizeof(cin))==-1)

{

perror("can&#39;t connect!");

exit(1);

}

printf("input a message:\n");

fgets(buf,sizeof(buf),stdin);

if((n=send(sd,buf,sizeof(buf),0))==-1)

{

perror("can&#39;t send message!");

exit(1);

}

if((n=recv(sd,buf,sizeof(buf),0))==-1)

{

perror("receive error!");

exit(1);

}

printf("response from server:%s",buf);

close(sd);

}