LAN with DHCP in a Linksys router, can't ping local machines

I have a LAN with DHCP in a linksys WRT54GL router, and three clients, (say ADS1, ADS2, ADS3) each of which has full internet access, none of which can see the others.

Each has hostname set properly in both /etc/hosts and /etc/sysconfig/network, e.g.

[ads@ADS1 etc]$ cat hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost ADS1

[ads@ADS1 etc]$ cd sysconfig
[ads@ADS1 sysconfig]$ cat network
NETWORKING=yes
HOSTNAME=ADS1
[ads@ADS1 sysconfig]$

Same for the others. But the names ADS1, ADS2, and ADS3 are not recognized by ping or anything else.

[ads@ADS1 $ ping ADS2
ping: unknown host ADS2
[ads@ADS1 sysconfig]$

What am I missing?

Thanks.

-Al


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