Scp to Synology DSM file system will use SFTP, not through SSH(default port: 8022), so you should use port 9022 (default port for SFTP) instead. And, you should use user space file system root as the target root. For example, you have a shared directory on /volume1/books/, you can use /books/ as the path, /volume1/books/ not works.
scp -P 9022 convert_to_utf8 username@synology_dsm_hostname:/books/collection/
Configuration Example:
service {
upnp2 {
acl {
rule 1 {
action allow
external-port 1024-65535
local-port 0-65535
subnet 192.168.199.0/24
}
rule 2 {
action allow
external-port 1024-65535
local-port 0-65535
subnet 192.168.5.121/32
}
rule 3 {
action deny
external-port 1024-65535
local-port 0-65535
subnet 192.168.0.0/16
}
}
listen-on eth1
nat-pmp enable
secure-mode enable
wan eth0
}
}
Looks like it is compatible with Synology DSM 7.