can't connect:no route to host.

[Altera_Forum]

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&#39;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&#39;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&#39;t connect:no route to host."  I don&#39;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);   }

[Altera_Forum]

please check the ethernet hardware address, they can not use the same number. 

check with ifconfig, and try to change it with ifconfig eth0 hw ether 11:22:33:44:55:66  replace the number with yours.  in case the ifconfig can not work, check the source of your ether driver to setup hw addr.

[Altera_Forum]

the ifconfig hw ether is not supported. 

please check kernel source arch/nios2nommu/kernel/setup.c after line 208. where it gets the hw addr.

[Altera_Forum]

--- Quote Start ---  originally posted by hippo@Sep 24 2006, 11:58 PM the ifconfig hw ether is not supported. please check kernel source  arch/nios2nommu/kernel/setup.c  after line 208. where it gets the hw addr. <div align='right'><{post_snapback}> (index.php?act=findpost&pid=18433)  --- quote end ---    --- Quote End ---    Yes,I checked the hw and both are the same,so the can&#39;t ping each other. I modified the source code according to you,and now I solved the problem. I have been busy for the days ,so I can only say thank you by now. thank you very much ,hippo!