Hello. On our roundcube installation I see the following error. When I send message, roundcube hangs with status "Sending message" for several minutes. Then I receive "Request time out". However, the message is sent. It's related to spell checker. I see that after sending message our roundcube host opens connection to spell.roundcube.net (443 port) and they are talking for a second:
12:01:24.804884 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [S], seq 3244734379, win 14600, options [mss 1460,sackOK,TS val 3808005355 ecr 0,nop,wscale 7], length 0 12:01:24.868230 IP plugins.roundcube.net.https > webmail-test.58972: Flags [S.], seq 3698264996, ack 3244734380, win 14480, options [mss 1460,sackOK,TS val 1331948192 ecr 3808005355,nop,wscale 6], length 0 12:01:24.868264 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [.], ack 1, win 115, options [nop,nop,TS val 3808005418 ecr 1331948192], length 0 12:01:24.869062 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [P.], seq 1:349, ack 1, win 115, options [nop,nop,TS val 3808005419 ecr 1331948192], length 348 12:01:24.932086 IP plugins.roundcube.net.https > webmail-test.58972: Flags [.], ack 349, win 243, options [nop,nop,TS val 1331948208 ecr 3808005419], length 0 12:01:24.935464 IP plugins.roundcube.net.https > webmail-test.58972: Flags [.], seq 1:1449, ack 349, win 243, options [nop,nop,TS val 1331948209 ecr 3808005419], length 1448 12:01:24.935492 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [.], ack 1449, win 137, options [nop,nop,TS val 3808005485 ecr 1331948209], length 0 12:01:24.935464 IP plugins.roundcube.net.https > webmail-test.58972: Flags [.], seq 1449:2897, ack 349, win 243, options [nop,nop,TS val 1331948209 ecr 3808005419], length 1448 12:01:24.935508 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [.], ack 2897, win 160, options [nop,nop,TS val 3808005485 ecr 1331948209], length 0 12:01:24.935473 IP plugins.roundcube.net.https > webmail-test.58972: Flags [.], ack 349, win 243, options [nop,nop,TS val 1331948209 ecr 3808005419], length 0 12:01:24.935478 IP plugins.roundcube.net.https > webmail-test.58972: Flags [P.], seq 2897:2975, ack 349, win 243, options [nop,nop,TS val 1331948209 ecr 3808005419], length 78 12:01:24.935519 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [.], ack 2975, win 160, options [nop,nop,TS val 3808005485 ecr 1331948209], length 0 12:01:24.937478 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [P.], seq 349:483, ack 2975, win 160, options [nop,nop,TS val 3808005487 ecr 1331948209], length 134 12:01:25.001537 IP plugins.roundcube.net.https > webmail-test.58972: Flags [P.], seq 2975:3225, ack 483, win 260, options [nop,nop,TS val 1331948226 ecr 3808005487], length 250 12:01:25.002056 IP webmail-test.58972 > plugins.roundcube.net.https: Flags [P.], seq 483:909, ack 3225, win 182, options [nop,nop,TS val 3808005552 ecr 1331948226], length 426 12:01:25.101188 IP plugins.roundcube.net.https > webmail-test.58972: Flags [.], ack 909, win 277, options [nop,nop,TS val 1331948251 ecr 3808005552], length 0
then connection hangs in ESTABLISHED state for several minutes.
How can I debug the issue? I see this behavior on both production and test server. Production server was running Roundcube Webmail 1.0-rc for a year now. It seems that errors started to occur this Monday...