In the upgrade from r11.0 0603 or from r11.6 sp00, /etc/inetd.conf retains the legacy txpi and txpis config statements:
txpi stream tcp nowait root /usr/lib/xcom/xcomtcp xcomtcp REMOTE 0
txpis stream tcp nowait root /usr/lib/xcom/xcomtcp xcomtcp REMOTE 0 SSL
added is, if it was not already there from r11.6 sp00 or if it came upgraded from r11.0 0603:
txpi6 stream tcp6 nowait root /opt/CA/XCOM/bin/xcomtcp xcomtcp REMOTE 0 NONE IPV6
txpis6 stream tcp6 nowait root /opt/CA/XCOM/bin/xcomtcp xcomtcp REMOTE 0 SSL IPV6
After upgrading to r11.6 SP01 the standard transmissions fail with a transmission error:
XCOMU0297E Error requesting header confirmation: Txpi 227: Socket received 0 bytes: partner closed socket. Last error: 0
The cause, is that the legacy /etc/inetd.conf for txpi and txpis statements are retained:
txpi stream tcp nowait root /usr/lib/xcom/xcomtcp xcomtcp REMOTE 0
txpis stream tcp nowait root /usr/lib/xcom/xcomtcp xcomtcp REMOTE 0 SSL
BUT ....
the /usr/lib/xcom symbolic links are for backwards compatibility to r11.0 release:
lrwxrwxrwx 1 root system 24 May 02 13:14 xcomend -> /opt/CA/XCOM/cmd/xcomend
lrwxrwxrwx 1 root system 23 May 02 13:14 xcomlp -> /opt/CA/XCOM/cmd/xcomlp
lrwxrwxrwx 1 root system 25 May 02 13:14 xcomntfy -> /opt/CA/XCOM/cmd/xcomntfy
lrwxrwxrwx 1 root system 23 May 02 13:14 xcompp -> /opt/CA/XCOM/cmd/xcompp
lrwxrwxrwx 1 root system 24 May 02 13:14 xcompre -> /opt/CA/XCOM/cmd/xcompre
In /usr/lib/xcom there is no symbolic link for xcomtcp -> /opt/CA/XCOM/bin/xcomtcp to allow the backwards compatibility and given that the upgrade is not changing /etc/inetd.conf causing the failure of the transfer.
XCOM r11.0 should be uninstalled cleanly, which includes clearing the /etc/inetd.conf file and refreshing the inetd service before installing r11.6 SP01.
See the online documentation CA XCOM Data Transport Installation and Upgrading to provide the proper upgrade instructions.
A few insights: