Synology disconnects router periodically
I have the following home network:
- Synology DS411+ (DSM 5.2)
- Cisco DCP3825 router
- Linksys WRT54GS running in gateway mode
Ever since I installed the DS unit on the network, I've been experiencing intermittent network failures from the unit itself and on other laptops. These failures last ~30secs and occur seemingly randomly every few minutes. Here are some observations of the failure:
web browsers on local Linux laptops show "resolving host..." and fail to access sites
accessing the router via the browser or pinging it does not respond
torrents on the Synology unit are disconnected
other local machines are still accessible, including the Synology unit
accessing the Synology unit via my external IP no longer works
Android / iOS devices are not affected by the failure
When I disconnect the DS unit from the network, these problems disappear. I've tried disabling a number of services from the unit without success:
- Windows sharing
- IPv6
- HTTPS
One additional observation that may be related is that running the "External Access > Router Configuration" setup shows me that the unit detects TWO routers, not just one, even though my WRT54GS is in gateway mode.

I need help to diagnose this problem and resolve it. Thanks!
networking nas synology
add a comment |
I have the following home network:
- Synology DS411+ (DSM 5.2)
- Cisco DCP3825 router
- Linksys WRT54GS running in gateway mode
Ever since I installed the DS unit on the network, I've been experiencing intermittent network failures from the unit itself and on other laptops. These failures last ~30secs and occur seemingly randomly every few minutes. Here are some observations of the failure:
web browsers on local Linux laptops show "resolving host..." and fail to access sites
accessing the router via the browser or pinging it does not respond
torrents on the Synology unit are disconnected
other local machines are still accessible, including the Synology unit
accessing the Synology unit via my external IP no longer works
Android / iOS devices are not affected by the failure
When I disconnect the DS unit from the network, these problems disappear. I've tried disabling a number of services from the unit without success:
- Windows sharing
- IPv6
- HTTPS
One additional observation that may be related is that running the "External Access > Router Configuration" setup shows me that the unit detects TWO routers, not just one, even though my WRT54GS is in gateway mode.

I need help to diagnose this problem and resolve it. Thanks!
networking nas synology
it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,/etc/resolv.confhasnameserver 127.0.1.1and/etc/dhcp/dhclient.confhassupersede domain-name-servers 8.8.8.8 8.8.4.4;
– infojunkie
Nov 7 '15 at 6:56
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01
add a comment |
I have the following home network:
- Synology DS411+ (DSM 5.2)
- Cisco DCP3825 router
- Linksys WRT54GS running in gateway mode
Ever since I installed the DS unit on the network, I've been experiencing intermittent network failures from the unit itself and on other laptops. These failures last ~30secs and occur seemingly randomly every few minutes. Here are some observations of the failure:
web browsers on local Linux laptops show "resolving host..." and fail to access sites
accessing the router via the browser or pinging it does not respond
torrents on the Synology unit are disconnected
other local machines are still accessible, including the Synology unit
accessing the Synology unit via my external IP no longer works
Android / iOS devices are not affected by the failure
When I disconnect the DS unit from the network, these problems disappear. I've tried disabling a number of services from the unit without success:
- Windows sharing
- IPv6
- HTTPS
One additional observation that may be related is that running the "External Access > Router Configuration" setup shows me that the unit detects TWO routers, not just one, even though my WRT54GS is in gateway mode.

I need help to diagnose this problem and resolve it. Thanks!
networking nas synology
I have the following home network:
- Synology DS411+ (DSM 5.2)
- Cisco DCP3825 router
- Linksys WRT54GS running in gateway mode
Ever since I installed the DS unit on the network, I've been experiencing intermittent network failures from the unit itself and on other laptops. These failures last ~30secs and occur seemingly randomly every few minutes. Here are some observations of the failure:
web browsers on local Linux laptops show "resolving host..." and fail to access sites
accessing the router via the browser or pinging it does not respond
torrents on the Synology unit are disconnected
other local machines are still accessible, including the Synology unit
accessing the Synology unit via my external IP no longer works
Android / iOS devices are not affected by the failure
When I disconnect the DS unit from the network, these problems disappear. I've tried disabling a number of services from the unit without success:
- Windows sharing
- IPv6
- HTTPS
One additional observation that may be related is that running the "External Access > Router Configuration" setup shows me that the unit detects TWO routers, not just one, even though my WRT54GS is in gateway mode.

I need help to diagnose this problem and resolve it. Thanks!
networking nas synology
networking nas synology
edited Sep 17 '18 at 18:46
Hennes
59.3k793144
59.3k793144
asked Nov 7 '15 at 5:28
infojunkieinfojunkie
15117
15117
it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,/etc/resolv.confhasnameserver 127.0.1.1and/etc/dhcp/dhclient.confhassupersede domain-name-servers 8.8.8.8 8.8.4.4;
– infojunkie
Nov 7 '15 at 6:56
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01
add a comment |
it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,/etc/resolv.confhasnameserver 127.0.1.1and/etc/dhcp/dhclient.confhassupersede domain-name-servers 8.8.8.8 8.8.4.4;
– infojunkie
Nov 7 '15 at 6:56
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01
it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,
/etc/resolv.conf has nameserver 127.0.1.1 and /etc/dhcp/dhclient.conf has supersede domain-name-servers 8.8.8.8 8.8.4.4;– infojunkie
Nov 7 '15 at 6:56
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,
/etc/resolv.conf has nameserver 127.0.1.1 and /etc/dhcp/dhclient.conf has supersede domain-name-servers 8.8.8.8 8.8.4.4;– infojunkie
Nov 7 '15 at 6:56
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01
add a comment |
1 Answer
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accessing the Synology unit via my external IP no longer works
This is your problem. For ease of use the DS units(and some others) use UPnP to try and intercept WAN traffic so that you can remotely access them. This isnt really the right way to do things, it should be statically assigned an address and the required ports forwarded, but thats not home user friendly.
- Disable remote access features("cloud") on Synology, reboot it, test to ensure stable
- Manually configure remote access features and use port forwards to allow access. Ideally you should NOT use port 80/443.
NB: Your DCP3825 may also be a lot more stable if you add a small fan to it like its sister model the 3925, one of the components loves to overheat.
Source: Working L1 for a large ISP.
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
add a comment |
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1 Answer
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1 Answer
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votes
accessing the Synology unit via my external IP no longer works
This is your problem. For ease of use the DS units(and some others) use UPnP to try and intercept WAN traffic so that you can remotely access them. This isnt really the right way to do things, it should be statically assigned an address and the required ports forwarded, but thats not home user friendly.
- Disable remote access features("cloud") on Synology, reboot it, test to ensure stable
- Manually configure remote access features and use port forwards to allow access. Ideally you should NOT use port 80/443.
NB: Your DCP3825 may also be a lot more stable if you add a small fan to it like its sister model the 3925, one of the components loves to overheat.
Source: Working L1 for a large ISP.
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
add a comment |
accessing the Synology unit via my external IP no longer works
This is your problem. For ease of use the DS units(and some others) use UPnP to try and intercept WAN traffic so that you can remotely access them. This isnt really the right way to do things, it should be statically assigned an address and the required ports forwarded, but thats not home user friendly.
- Disable remote access features("cloud") on Synology, reboot it, test to ensure stable
- Manually configure remote access features and use port forwards to allow access. Ideally you should NOT use port 80/443.
NB: Your DCP3825 may also be a lot more stable if you add a small fan to it like its sister model the 3925, one of the components loves to overheat.
Source: Working L1 for a large ISP.
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
add a comment |
accessing the Synology unit via my external IP no longer works
This is your problem. For ease of use the DS units(and some others) use UPnP to try and intercept WAN traffic so that you can remotely access them. This isnt really the right way to do things, it should be statically assigned an address and the required ports forwarded, but thats not home user friendly.
- Disable remote access features("cloud") on Synology, reboot it, test to ensure stable
- Manually configure remote access features and use port forwards to allow access. Ideally you should NOT use port 80/443.
NB: Your DCP3825 may also be a lot more stable if you add a small fan to it like its sister model the 3925, one of the components loves to overheat.
Source: Working L1 for a large ISP.
accessing the Synology unit via my external IP no longer works
This is your problem. For ease of use the DS units(and some others) use UPnP to try and intercept WAN traffic so that you can remotely access them. This isnt really the right way to do things, it should be statically assigned an address and the required ports forwarded, but thats not home user friendly.
- Disable remote access features("cloud") on Synology, reboot it, test to ensure stable
- Manually configure remote access features and use port forwards to allow access. Ideally you should NOT use port 80/443.
NB: Your DCP3825 may also be a lot more stable if you add a small fan to it like its sister model the 3925, one of the components loves to overheat.
Source: Working L1 for a large ISP.
answered Nov 7 '15 at 11:07
Linef4ultLinef4ult
3,6701021
3,6701021
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
add a comment |
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Thanks. I am already running with QuickConnect disabled (if that's what you mean by "cloud") and port forwarding done manually on the router. I have added info describing an additional gateway device in the network that may play a role in the problem.
– infojunkie
Nov 7 '15 at 17:12
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
Regarding the fan: the previous owner had installed an additional one.
– infojunkie
Nov 7 '15 at 17:14
add a comment |
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it sounds like your DNS is being interrupted. What devices do you have DHCP servers on, and do any of your devices point to the NAS for dns lookup?
– Frank Thomas
Nov 7 '15 at 6:01
The only enabled DHCP server is on the router. The one on the NAS is disabled. The NAS has a static IP address, pointing to the router as gateway. On my Ubuntu laptop,
/etc/resolv.confhasnameserver 127.0.1.1and/etc/dhcp/dhclient.confhassupersede domain-name-servers 8.8.8.8 8.8.4.4;– infojunkie
Nov 7 '15 at 6:56
I've also changed the WRT config to "router" with no change in behaviour.
– infojunkie
Nov 7 '15 at 19:43
Disabling the WRT completely also did not modify the behaviour, or the report above.
– infojunkie
Nov 8 '15 at 21:01