I think I've fixed the caget/caput issue. Rana's observation that pinging the IP directly was faster than pinging the hostname set me on a path of googling which informed making the following changes to the DNS setup on chiara (specifically, informed by this thread: http://www.dslreports.com/forum/r11836974-BIND-slow-to-reply-over-LAN-Solved)
/etc/bind/named.conf.local has these lines:
zone "martian" IN {
type master;
file "/etc/bind/zones/martian.db";
};
zone "113.168.192.in-addr.arpa" {
type master;
file "/etc/bind/zones/rev.113.168.192.in-addr.arpa";
};
The first zone command links hostnames like c1lsc to an IP like 192.168.113.62, but apparently in the second, we need to do the inverse. So, for each line in martian.db like
c1lsc A 192.168.113.62
I added a line in rev.113.168.192.in-addr.arpa like so:
62 IN PTR c1lsc.martian
This seems kind of silly, but now if you do the host command from a workstation, it can find the hostname associated with an IP.
controls@pianosa|~ > host 192.168.113.62
62.113.168.192.in-addr.arpa domain name pointer scipe12.martian.113.168.192.in-addr.arpa.
62.113.168.192.in-addr.arpa domain name pointer c1lsc.martian.113.168.192.in-addr.arpa.
[At this point, note that we have a bunch of duplicate entries in https://wiki-40m.ligo.caltech.edu/Martian_Host_Table with these scipe## hostnames. What are these for?]
Now (edited for brevity):
controls@ottavia|~ > ping -c 5 -D c1sus
PING c1sus.martian (192.168.113.85) 56(84) bytes of data.
<SNIP>
--- c1sus.martian ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 3997ms
rtt min/avg/max/mdev = 0.051/0.075/0.114/0.028 ms
controls@ottavia|~ > ping -c 5 -D 192.168.113.85
PING 192.168.113.85 (192.168.113.85) 56(84) bytes of data.
<SNIP>
--- 192.168.113.85 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 3998ms
rtt min/avg/max/mdev = 0.052/0.130/0.380/0.127 ms
controls@pianosa|~ > time caget C1:LSC-XARM_GAIN
C1:LSC-XARM_GAIN 0.015
real 0m0.039s
controls@pianosa|~ > time caput C1:LSC-XARM_GAIN 0.0151
Old : C1:LSC-XARM_GAIN 0.015
New : C1:LSC-XARM_GAIN 0.0151
real 0m0.054s
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